摘要:

FEBRUARY 1905. Vol. XXX. No. 347. ELECTRIC FURNACES FOR LABORATORY USE. BY BERTRAM BLOUNT F.I.C. (Read at the Meeting December 7 1904.) HEATING by gas is not always convenient for laboratory use because it is difficult to apply the heat so exactly that the object to be heated receives the greater part of the heat. If the thermal units generated by an ordinary Bunsen burner be computed, and those strictly necessary to raise the temperature of the object to be heated be reckoned it will be found that the efficiency of the arrangement will be of the order of magnitude of 1 per cent. This would be a small matter were it not that the whole of the gas thus wasted produces its proper quantities of water carbonic acid and the like and fouls the atmosphere of the laboratory to a corresponding extent.When a high temperature is needed the gas must be consumed at a greater rate and a blast is necessary. This requires bellows or aome form of blower and these arc troublesome and noisy. The peculiar quality of electric heating is the ease with which it may be directed to the place where it is needed and the precision of its regulation. The object to be heated may be raised to any determined temperature and this tempera-ture may be maintained indefinitely. Seeing that a sufficient current put through a suitable resistance will heat the resistance and anything with which it may be i 30 THE ANALYST. contact to a temperature dependent solely on the current and the drop of voltage between the points where the current enters and leaves the resistance it would appear to be a simple matter to devise a furnace for laboratory use.The obvious method of heating a tube crucible or muffle by wrapping round it fine platinum wire and passing an appropriate current fails for the reason that unless the temperature is very moderate the wire will be heated to a point where it is ductile and the necessary slight tension on it will draw it down in places. These But as generally happens in practical affairs little difficulties crop up. attenuated points will become hotter than the rest of the wire and will finally fuse. The difficulty of using wire is much increased when as is usual the current to be employed is supplied at a moderately high pressure-e.g. 200 volts. I n this case the section of the wire must be small and the risk attending its reduction in section, consequent on some casual tension will be proportionally greater.This difficulty has been met and overcome by Hersus of Hanau who conceived the excellent idea of substituting for the wire a strip of platinum foil. The section of this is naturally, the same as that of a wire to convey the requisite current but the fact that it is flat allows it to sit close upon the surface to be heated. Hence it will not stretch an THE ANALYST. 31 break as will a wire because it is well supported by the surface on which it is wrapped and also because the close contact of all its parts with that surface allows the transference of heat to take place so rapidly that the temperature of the heating-strip is never much higher than that of the object to be heated.These simple con-siderations have been philosophically applied by Hersus. His apparatus consists of a tube of specially refractory porcelain the so-called Macquart’s Masse made by the Royal Porcelain Works of Charlottenburg round which is wrapped a strip of platinum foil so thin that it may be broad and yet possess the requisite resistance. The strip is 13 millimetres in width for 100 volts and 7 millimetres for 200 volts and 0007 inillimetre in thickness. A tube furnace 20 centimetres in length requires only a small weight of platinum ; for example 6 grammes. I n Heraeus’s apparatus the resistance is wrapped round a tube which serves as a muffle for an internal tube. It can be used for all ordinary tube-furnace purposes, such as the ultimate analysis of organic substances and the combustion of carbon in steel.The temperature can be raised to any point short of the fusion of the Y F P P F FIG. 1.-sECTION OF “ DIRECTLY-PACKED ” FURNACE. C C Copper end plates ; F fireclay or porcelain outer tube ; R resistance mixture ; P porcelain inner tube. platinum and the porcelain and its regulation is easy. The apposition of the platinum to the porcelain is so good that fracture of the former is not likely to occur. I n short this apparatus could scarcely be bettered if it were not somewhat slow in cooling ; in consequence successive operations occupy a relatively long time. This slowness is due chiefly to the excellent non-conducting sheath of the furnace. If the envelope were less efficient some waste of current would occur but would be more than balanced by greater speed of working.It seemed possible to construct an effective resistance furnace on somewhat different lines from those adopted by Hereus. I n my own work I required a furnace for the determination of oxygen in copper which could be rapidly heated to the fusing-point of the metal. Mr. Owen Lucas was good enough to suggest that it might prove practicable to prepare an annular resistance of retort carbon which would serve to heat a porcelain tube. The idea was put into working shape in my laboratory and finally took the following form : The first form of furnace was one in which the porcelain tube to be heated was surrounded with a similar but rather wider tube and the annular space between them was packed with a resistance material.A porcelain tube (Fig. 1) 9 inch external diameter was placed inside a shorte 32 THE ANALYST. and wider porcelain or fireclay tube about 1 inch in internal and 14 inches in external diameter and 7 inches long so that about 3 inches of the inner tube projected at each end. The space between the two tubes was filled with the resistance material, consisting of retort carbon mixed with varying percentages of siloxicon or carborun-durn the current being conducted to this material by two short tubes of copper which fitted closely into the space between the two tubes. This type of furnace required a maximum current of G ampires. Afterwards it was found that the muffle principle used by Heraeus was prefer-able and a furnace of this type was constructed.The essential parts of this latter form of furnace are two concentric fireclay tubes surrounding but not actually touching that part of the porcelain tube to be heated. The resistance material is packed between these two fireclay tubes the current being led in by means of an annular copper disc at each end which is pro-(Fig. 2.) &- __ - - _ _ ~ - -7y4* __ -. - - - -- -.-! PIG. 2.-sECTIOS OF " INDIRECTLY-PACKED " TUBE. A Clamps ; B asbestos cloth ; C copper terminals ; F fireclay tubes ; D pieces of fireclay ; B resistance mixture ; P porcelain tube ; U uralite discs. vided with a short cylindrical projection fitting closely in between the two tubes so as to make good contact with the resistance material. If the space between the two tubes is very narrow this may consist of pure retort carbon only; otherwise for wider spaces which take more of the material its resistance may be increased by adding varying amounts of siloxicon.Carborundum has also been used for this purpose but does not answer as well as siloxicon as its resistance falls extremely rapidly at high temperatures apparently approaching that of the carbon. The two tubes which form the furnace proper are surrounded by two other wider fireclay tubes which serve merely to insulate the heat. They may be covered with asbestos wrapping still further to retain the heat. The ends of the furnace are made of uralite discs which also support the porcelain tube to be heated. With this apparatus a piece of copper weighing 15 to 20 grammes can be fuse THE ANALYST.33 in fifteen minutes; and after its fusion and the reduction of the oxide it contains the whole contrivance is cool enough to allow of the removal of the copper and the insertion of another sample in the space of twenty minutes. With a gas furnace the time occupied is much the same but the surplus heat and waste gases are serious drawbacks. I n the description given some time ago (ANALYST xxi. 57) of my method of determining oxygen in copper the details of working are described; one of these is the purification of the hydrogen destined to reduce oxides in the copper by passing it over heated platinized asbestos. For convenience' sake and to make the apparatus inde-pendent of clumsier methods of heat-ing this too has been done electrically.The platinized asbestos is contained in a tube which is coiled round a glow lamp and protected by an insulating sheath. It is kept hot enough to induce the combination of any small quantity of oxygen that may be present in the hydrogen. Formerly when gas was used this essential precaution had to be secured by a bulb-tube heated by a Bunsen burner. The difference in point of convenience is considerable. The apparatus as set up for use is shown in Fig. 3 and the photograph on p. 30. I have described a particular use of a particular form of electric furnace for laboratory purposes. The use may be extended to many operations and the form may be modified accordingly. The fundamental idea is the adoption of a resista.nce material which can be packed into an annular space between two porcelain tubes and the resistance of which can be replatled by its cross-section and by its composition which is so ready to hand and so cheap that any required furnace can be prepared at short notice.I t seems to me that almost all common laboratory heating operations woul 34 THE ANALYST, be best done electrically; the chemist himself can hardly be expected to devise detailed methods but the instrument -maker might well try. I desire to thank Mr. A. G. Levy and Mr. H. E. Course for their valuable aid. DISCUSSION. The PRESIDENT (Mr. Fairley) said that a simple method of electrically heating a liquid-namely by the immersion in it of an incandescent lamp-had been recently described before the Nottingham section of the Society of Chemical Industry (Journal of the Society of Chemical Industrry 1904 xxiii.p. 1137). The method was particularly applicable to distillation. Electricity would no doubt in the future be widely used for heating purposes. I n his own district only an alternating current was supplied. This however could be used with special appliances or could be transformed. Mr. RICHMOND inquired whether Mr. Blount had used an alternating current in any of his experiments. The heating effect of the alternating current would be the same as that of the direct current but the direct current arc was far more destructive than the alternating current arc and one would require to pay more attention to the contacts. Mr. I;. MYDDELTON NASH asked whether the tube containing the boat could not itself be surrounded by the platinum foil thus avoiding the use of two tubes and consequent loss of available heat.Mr. CHAPMAN asked whether with the furnace shown it was easy to arrange for progressive distributed or divided heating such as was of course necessary in ordinary ultimate organic analysis. For some years he had been making use of electric water-baths in his laboratory for the distillation of ether and other inflam-mable liquids with the greatest possible advantage. Mr. SUTHERLAND said that he would have liked to hear more about Mr. Blount’s experience with siloxicon with regard to its general properties and use for lining large furnaces cost etc. I t was said to be harder than carborundum than which it was he believed somewhat dearer.Its price was about 4d. per pound. He would also like to ask Mr. Blount whether the principles of the furnaces he had described had been successfully applied to the heating of furnaces for crucibles and muffles or larger furnaces. Mr. BLOUNT said that he must confess some ignorance with regard to the use of alternating currents for heating. He believed that alternating currents had been tried in these furnaces and that the difference in their operation with direct and with alternating currents was small. The number of watts being the same the heat generated must be the same and one would hardly expect those differences which might be observed in the case of arcs to be reproduced in heating through a resistance. The only possible alteration in working that could be foreseen would be some diflerence at the points of contact of the terminals with the resistant material or of the resistant material itself and clearly that difference if it existed would apply only to his form of furnace and not to that of Heraeus in which the conductor was continuous.With regard to the use of a single tube perhaps in going through the paper he had not been sufficiently explicit. He had meant to make it clear that the There should be a large field in this direction for electric heating THE ANALYST. 35 furnace as he had modified it was originally a single-tube furnace the heating being direct on the tube it was desired to heat. When a platinum conductor was used a single tube was not efficient because for ordinary operations with gases it must be glazed and the platinum foil if wound on a glazed tube ate into the glaze and was soon destroyed.The tube must be biscuit porcelain which was not impervious so that the porcelain tube must be used as a muffle. In the second form of his (the author’s) furnace a similar muffle was adopted using fireclay instead of biscuit porcelain. The furnace was quite capable of being broken up into divisions to secure the distributed effects mentioned by Mr. Chapman. Indeed Heraeus had already made furnaces in sections and in such furnaces ultimate analyses could be performed as easily as in an ordinary furnace though the process was somewhat slower. Mr. SUTHERLAND asked whether a tube glazed on the inside only could not be used. Mr. BLOUNT said that he had tried the use of a tube glazed on one side but had not found it to be satisfactory.Mr. Sutherland had asked about siloxicon which was a very interesting substance. I t was not conspicuous for its hardness its real value lay in its refractoriness. As a furnace lining it was considerably used and, although not so stable at high temperatures as carborundum was well adapted for lining furnaces which were subjected not only to high temperatures but to the action of reducing or oxidizing agents. It was being employed as a protective lining for rotatory cement kilns which were subjected to as heavy a wear as any sort of furnace. As t o its price he could not say much but it must be less than that of carborundum which was very moderate-about 620 a ton. The price of 4d. per pound mentioned by Mr. Sutherland would therefore seem to have been a retail one. He agreed with Mr. Sutherland in thinking that there mas a large field open in the direction of large furnaces and furnaces for crucibles. He thought however that the devising of such appliances might safely be left to the instrument makers. The road into that field had been opened by Herzus and in a smaller degree by his own work. In reply to further questions put by Mr. HEHNER and by Mr. SUTHERLAND, Mr. BLOUNT said that in the analysis he had made of the siloxicon the carbon had been determined by combustion with lead chromate. The silicon had been directly determined and the oxygen was by difference. The siloxicon however was not likely to burn away when used as a furnace lining nothing short of actual fusion with a substance like lead chromate would affect it

ISSN:0003-2654    

DOI:10.1039/AN905300029b

出版商:RSC    

年代:1905

数据来源: RSC

摘要:

36 THE ANALYST. BRANDY. BY OTTO HEHNER. (Read at the Meeting January 11 1905.) ON November 29 1902 there appeared as a supplement to the Lancet a report of a Special Analytical Commission on ( I Brandy its Production as Cognac the Present Position of the Industry in the Charentes and the Supply of Genuine Brandy to this Country.” This report appears to have been the stimulus which caused certain Public Analysts to take up the examination of commercial brandies under the Sale of Food Acts. Although the report of the Lancet Commission contained not only nothing that should have been novel to any well-read Public Analyst but gave much less information than had been obtainable for a t least ten years previously it seems to have directed attention to what is undoubtedly a most important question.It is our business as Public Analysts to carry out the provisions of the Sale of Food and Drugs Acts and to see that when the public demands any article of food or drink, an article of the “nature substance and quality demanded” is supplied. I t is equally our business as scientific men to act up to the scientific knowledge available, but not to go one step beyond and pretend to do that which is in our present state of knowledge impossible. It will be seen that the Lancet report although dealing with brandy concerned itself solely with its production at Cognac and with the position of the brandy industry in the Charentes the home of the Cognac industry. That is to say it dealt with that variety of brandy which is known as ( ( cognac.” If all brandy were cognac, if only that which is produced in the Cognac district and by the Cognac methods had the right to be called (‘ brandy,” the matter would be a comparatively simple one.We are all agreed that the term ‘(cognac” applies only to a distillate obtained from wine and from nothing else cont.aining the full flavour peculiar to cognac-a flavour only obtainable in a product resulting in a more or less primitive manner by pot-still distillation without much fractionation or purification. Opinions are and may be legitimately divided on the question whether ‘‘ cognac ” nowadays belongs only to the product obtained as described in the Cognac district itself or whether the term has lost its geographical significance as ( ( Munich beer,” ‘‘ Yorkshire pudding,” or ‘I Bath bun ” have.The term (‘ brandy ” is obviously not synonymous with ‘( cognac,” for in the immense wine industry-one of the greatest agricultural industries of the world-wine distillates are obtained which could not possibly be classed or sold as “ cognacs,” and yet possess wine flavour or bouquet. Such distillates are known in this country as I take this term to be a corruption of the German word “Branntwein,” literally ( ( burnt wine ”-a wine distillate. Many generations ago before Continental nations had learned to prepare distilled alcoholic beverages from grain or other starchy material all ‘( Branntwein ” was a wine distillate whilst now it only means a distilled alcoholic beverage mostly made from grain but not necessarily from that only. fire-water ” of the Red Indian.But while both the French and Germans were satisfied with the gradual brandy.” It corresponds to (‘ eau de vie ” of the French or th THE ANALYST. 37 drifting of the respective terms ‘‘ eau de vie ” and (( Branntwein ” to beverages not necessarily made from wine-just as we apply the word “ vinegar ” no longer to acidified wine but to acid liquors of other derivation-the English purchaser as of old attached the term ‘‘ brandy ” to the wine distillate only. Brandy not being an English production it is perhaps natural that he should remain behind in the knowledge that the industry was changing. I will not for the moment stop to consider whether the English purchaser is reasonable in attaching a meaning to a term which it no longer possesses in other countries but will for the present put myself upon the standpoint of the purchaser, only expressing my opinion that his view is old-fashioned narrow-minded and unreasonable.In the case of the national distilled alcoholic beverage ‘‘ whisky ”-which once upon a time was the liquor obtained from fermented malt-wort only, distilled from pot-stills-the nation has not objected to the widening of the term, substances other than malt being used and scientific rectification stills having largely taken the place of the old pot-stills. Differences in flavour and in com-position have of course followed the alteration in manufacture. In the case of beer the changes are wider still; there is not in fact a manufactured article of food or drink where changes in preparation and in composition are not continually being made.Brandy for the purposes of my argument shall form an exception for the purchaser however ignorant and prejudiced is entitled to his prejudice and tihe vendor must supply him with (‘ the article demanded.” We analysts have no other means than chemical or physico-chemical of ascertaining whether an article is ‘‘ genuine ” or not and for us the whole question is an analytical one. We obviously cannot distinguish pure alcohol derived from wine from that derived from ’the potato any more than we can differentiate between sugar made from the cane and that made from beet. We have nothing to go by but the concomitants of the alcohol the ‘‘ impurities ” which give to the alcohol its aroma flavour and character.Apart from solid substances that have been taken up from the wood of the casks or that have been intentionally added for colouring or sweetening the (‘ impurities ” of spirits belong to five or six classes of bodies-alcohols other than ethylic ; acids mainly acetic ; aldehydes chiefly ethylic ; ethers ; basic substances; and furfural. Every one of these classes contributes ite quota towards the character of the beverage probably also towards its physiological properties. Since 1883 when Nessler and Barth correctly stated (Zeitsch. Anal. Chenz., vol. xxi. p. 33) that hardly any chemical data existed for the examination of distilled beverages fair progress has been made in the working out of methods for detecting and determining the amounts of the various cZasses of substances above enumerated, although as we all know much remains to be done.But no advance worth record-ing has been made-nay barely has the attempt been made-to differentiate between the individual members which make up each class of these ‘‘ impurities.” Nor is there much hope that such differentiation of closely-allied substances the sum total of which amounts to almost intangible traces will be practicable for the purposes of the Public Analyst. Let us take only the ‘‘ higher alcohols,” or ‘( fuse1 oils,” which generally form the larger proportion of the “impurities.” I t is known that the higher the molecular weight of an alcohol the greater its toxicity. It is also know 38 THE ANALYST. that secondary alcohols are more noxious than primary and unsaturated more than saturated; yet the analyst must content himself with determining as best he may, the sum total of the higher alcohols leaving altogether aside the question whether these consist of harmless or noxious members of the group.Again the analyst can, with satisfactory accuracy determine the amount of alkali required to hydrolyse those constituents which are called ‘‘ esters,” and to calculate the alkali consumed into any imaginary member of the (‘ ester ” group ; but whether the constituents thus measured consist of valueless ethyl acetate or of complex and valuable members is beyond his ken; and so on with each one of the groups. A vast mass of analytical data valuable as far as they go has however gradually accumulated. Hundreds of analyses of brandy and of other similar beverages have been published during the last ten or more years mainly by Girard and Cuniasse Rocques Sell, Mastbaum Allen Schidrowitz and many others ; and pages of figures containing analyses as full as practicable-quite a8 full as the few of the Lancet Com-missioner (some of which are quoted from French sources)-are contained in Koenig’s magnificent collection (‘( Chemie der Menschlichen Nahrungs und Genussmittel,” fourth edition).New series of analyses are continually being published the latest being an admirable contribution by Karl Windisch (Zeitsch. U?zters. Nahrungs zcnd Gem.~ss-mittel vol. viii. October 1904 pp. 465-505). This closely-reasoned paper is worthy of very attentive study. Among other things Windisch disposes once more of the suggestion which has been made by Loock (Zeitsch.ofentl. Chem. 1900 vol. vi., p. 397) that all genuine wine distillates contain furfural whilst silent spirits were said to be free from it. Furfural is shown to be an accidental product of the decomposi-tion of the pentoses; it is often-but by no means always-present in brandies. As a measure of genuineness it is useless. Windisch further discusses the much-debated claims made by Girard and Cuniasse Rocques and other French chemists for the coefficient of impurities,” the sum total of volatile acids esters aldehydes higher alcohols and furfural expressed in parts per 100,000 of the water-free sample. The coefficient of impurity for real cognac is alleged to be never less than 300 according to Girard and Cuniasse and to Lusson not less than 340 while Rocques further claims that pure wine distillate contains approximately equal quantities of higher alcohols and of esters.As regards the latter relation I may at once point out that in Rocques, Analyse des Alcools et des Eaux de Vie,” analyses of real cognacs are given showing this proportion to vary from 0.9 to 2.5 (higher alcohols divided by esters), while in other real brandies-not cognacs-the proportion varies from 0.43 to 2.92. As regards the co-efficient of impurities,” it may be worth while to quote the averages of all analyses of Girard and Cuniasse as given by Koenig (Zoc. cit.) p. 1511 etc. : Analytically therefore the fringe only of the subject has been touched. Industrial alcohols . . . Real cognacs . . . Normal cognacs .. . Artificial cognacs . . . , (fair quality) . , (imitation) . . . Commercial cognacs (known brands) . Marc brandies . . . Kirsch brandies . . . . ? I 9 . . . 9 , . . * . . . . . . . 17.6 486.3 473.3 257.3 57.8 852.1 238.5 401.5 448.6 64. THE ANALYST. 39 Rum . . . . . 690-5 . . . . . 593.9 Mixtures . . . . . 299-4 7 , , (artificial) . . . 104.6 Cider brandy . . . . 710-2 Whisky . . . . . 409.4 The figures for ( ( real cognacs ” vary from 259.6 (a sample marked ( ( Aunis, good but not warranted ”) to 1174.3 (a very old cognac) while the commercial cognacs” show variations from 74.6 to 703.2. I t may be that the L‘commercial cognacs ” include admixtures ; but there is no evidence to that effect.A sample, twenty years in bottle and therefore presumably genuine showed a coefficient of “impurity ” of 131.7. The limit of 300 cannot therefore be maintained even for the cognacs analysed by MM. Girard and Cuniasse. I n an article like brandy it is practically impossible to furnish unexceptionable evidence of its purity. No single person would ever be in a position to follow its production from the vineyard to the bottle. On the other hand the classification into dl real cognacs,” 1 L normal cognacs,” ‘( commercial cognacs,” and “ artificial cognacs,” adopted by Girard and Cuniasse is altogether arbitrary and as a rule based upon nothing better than the figures obtained by analysis and as the fixation o€ a limit of “ impurities ” is an arbitrary process this procedure begs the whole question.Similarly referring to Mr. Vasey’s book on “ Analysis of Potable Spirits,” the classification into types of brandies (which ought really to be types of cognacs) and types of blended spirits rests upon insufficient evidence. For brandies of sources other than those of the cognac district it has been conclusively proved upori evidence which is exceedingly strong that the coefficient of ‘‘ impurity ” is quite inapplicable. Thus Mastbaum (Zeitsch. Unters. Nahrunqs zbnd GenusmitteZ 1903 pp. 56 57) analysing and recording the results of twenty Portuguese brandies of authenticated origin and following Girard’s methods of examination finds the I n nine samples out of twenty it was less than 300 while the relation of esters to higher alcohols instead of being unity or thereabouts varied from nine to one.Mastbaum also finds furfural absent in some of these samples among these the very finest. The ‘( coefficient of impurity ” has now however officially received its quietus a report by a committee appointed by the French Minister of Commerce by a decree of March 22 1904 (which report was published in the Noniteur Oficiel de Commerce of June 30 1904 and is commented upon in Nature of November 3 1904) showing that while ordinarily the coefficient in cognacs and fine champagne ranges between 275 and 450 it is less in Armagnac brandies while in those from the Midi and Algeria it varies from 25 to 500. What possible value can attach to an analytical factor which varies from 25 to nearly 1,200 ? The French Committee therefore (‘ are unable to recommend that any limit should be fixed,” and they as other observers before them reported that (‘ expert tasting (ddgusiatiofi) must be considered as an indispensable complement of chemical analysis.” Therefore proof of genuineness cannot easily be obtained.coefficient of impurity ” to vary from 107.5 to 977 40 THE ANALYST. The slightest consideration shows that immense variations in the ( ( coefficient of impurities” are bound to occur. By keeping large proportions of aldehydes are formed; when the brandy is made as it often is from wine that is more or less ( ( off,” variable amounts of acetic acid pass into the distillate and the acidity again, controls the amount of esterification. As regards the higher alcohols which mostly form a very large proportion of the total ‘( impurities,” these are for the most part not products of the alcoholic fermentation by yeasts at all but are formed after the chief fermentation is over by bacterial action upon carbohydrates (Emmerling, Berichte 1904 p.3535) under anaerobic conditions and their production is not under practical control of the vintner. But the manner of distillation more than anything else controls and is bound to control the composition of the distillate. If from a badly-fermented wine the spirit be distilled off by crude means large quantities of fusel oil and other products pass over-little from sound wines distilled, as they sometimes are in distilleries from the water or the brine bath. The first fractions of the distillate are naturally comparatively rich in ‘( impurities.” Experiments made by the Swiss Government show that when wine is distilled the fusel oil coefficient varies from 660 to 170 in successive fractions.The Lancet com-mission’s table on p. 1511 exhibits variations from 334 to 37. Taking all circum-stances into consideration it follows that the “ coefticient of impurities ” is largely an accidental quantity applicable under proper restrictions to products made in the same way from approximately uniform crude products but not applicable to all brandies alike nor useful for the purpose of fixing a standard under the Sale of Food and Drugs Act. The French originators of the coefficient knew this full well for with all their advanced knowledge of the present time they are in the same position as were Nessler and Barth in 1883 when they said (Zoc.cit.) ‘( Without doubt the sense of taste and smell of the connoisseur are better reagents for quality and purity of brandy than are chemical means,” a position confirmed by W. Fresenius 1890 (Zeitsch. anal. Chem. p. 283); again by Sell in 1892 (Arbeiten a.d. Kaiserl. Gesund-heitsamte vol. vi. p. 335) who warns the analyst that he cannot analytically prove with certainty the purity or impurity of any saniple but that he has also to consult his senses ; by Bersch (Ncxhrungs. GemwmitteZ vol. ix. 1895 p. 116) who insists upon the same thing and suggests that in every case involving a prosecution the judgment of the chemist must be confirmed by that of one or more tasting experts.In 1895 Rocques (Moniteur Scientg April) strongly recommends to combine chemical analysis with ddgustation-that is tasting and smelling the brandy in its concentrated form as well as diluted with warm water. Girard and Cuniasse recommend the same course and Koenig summing up in 1904 with the knowledge of all the analytical work published up to that time warns the chemist that taste and smell by experts afford a safer foundation for an opinion than does chemical analysis.” We judge nearly all our food-stuffs certainly all our ‘‘ Genussmittel,” as dis-tinguished from ‘‘ Nahrungsmittel,” by our senses of taste and smell and not by analysis. We cannot distinguish the cheapest from the most expensive wine by analysis ; I know of no analytical difference between a halfpenny and a one-shilling cigar nor between the cheapest tea and the finest.Flavours have been and are still in most cases beyond our analytical grasp THE ANALYST. 41 Having quoted the opinion of the above chemists who have specially concerned themselves with the analysis of brandy and other alcoholic distilled liquors I would contrast with it without further comment the position taken up by some Public Analysts in this country namely that the determination of the amount of ethers is sufficient to form a judgment upon which a vendor may be criminally prosecuted-nay further that this single determination justifies them in giving a definite certificate to the effect that a sample because deficient in ethers-judged by an imaginary limit-contains a definitely-stated percentage of spirit not derived from the grape.I t would be easy to quote from the hundreds of published brandy analyses numbers referring to ethers only and which show that these fluctuate as widely almost as the (‘ coefficient of impurities.” I n undoubtedly genuine brandies ether coefficients have been found as low as 18 and as high as 450. I myself have had in hand quite a number of brandies which I have received from responsible persons and with every assurance that they consisted of nothing but good commercial wine distillates and which yet contained far less than the limit of 80 which is associated with certain recent legal proceedings. Almost in every instance when a brandy not produced in France is examined the ether number is low and to say that a producer of a wine distillate in Algeria Spain Portugal California or Australia has no right to call his distillate a brandy ” would be as unreasonable as to suggest that the Russian peasant has no right to call the fat which he churns from his milk a butter simply because it sometimes differs in composition from that of the Australian or English producer.This position is emphasized by the necessity under which some analysts have lately found themselves of adopting as a definition of brandy “ an alcoholic liquid obtained from wine by distillation in pot-stilk.” It may well be that a wine distillate from pot-stills ” has a stronger and perhaps more valuable flavour than a product made from some other kind of still; but this I maintain is a question for the fancy of the consumer.It is interesting to inquire what is the probable reason for the selection of the ‘‘ ethers I’ out of the whole list of concomitants which chemists have found necessary to determine for forming the best possible judgment on a ‘‘ spirit.” I am firmly convinced that this selection is due mainly to prejudice. The chemist associates the term ‘ I ethers ” with pleasant-smelling aromatic substances. That the ethers ” contribute their quota towards the flavour of a brandy must be obvious; but that they are far removed from being the sole or even the main factors is apparent from the fact than when an alkaline hydroxide is allowed to act in the cold upon a brandy the aroma undergoes comparatively little change. For all other constituents which the analyst can determine no good case in favour of brandy can possibly be made out.I n the eyes of the public the Bench and especially in those of the Medical Profession it would not be considered a recommendation if they were told that brandy as a rule was exceptionally rich in fusel oil for fusel oil has for inany years past been associated in the public mind with all that is undesirable in spirituous liquors. Nor would it help to call in the assistance of furfural which is poisonous nor of aldehydes which are irritating and obnoxious. As brandy how-ever doubtless occupies a high position in the public opinion and as the mai 42 THE ANALYST. impurities present in it cannot; possibly be considered in any favourable light, especially from a medical point of view it is but a small step to attribute to the ethers virtues which they probably do not possess or for the possession of which not a particle of scientific evidence has ever been brought forward.In the various cases which have been before the police-courts of late an important feature of the prosecutions was the evidence of medical men who spoke eloquently about the medicinal properties of brandy which were alleged to reside in their ethers. As a matter of fact all unrefined spirits no matter from what source are comparatively rich in ethers. The difference in the ether content of brandy and of whisky is often insignificant whilst the quantity in rum is frequently very high. I t is highest of all in the very commonest of brandies made from the residues the skins and pips of the grapes from which the valuable juice has been expressed.In spite of medical opinion there is no doubt to my mind that the eft‘ects of a spirituous liquid reside in its alcohol and for all practical purposes in nothing else and that the function of the ‘‘ impurities ” is solely to give to the otherwise flavourless alcohol that zest which human beings require in all they eat or drink. It is quite well known that the best and most nutritious of diets is not tolerated unless it is properly flavourad. Dietaries that have been constructed with a disregard of that fact have led before now to catastrophes among prisoners and soldiers and culminated in deaths. As a machine will not run without lubricant although the latter adds nothing to the power so the flavour of food or drink facilitates the work of the animal machine.The consumer must ‘‘ like ” his food for it to agree with him. The one may prefer the flavour of whisky the other of brandy as regards his beverage but a chemical and scientific explanation cannot be given. For years the impression has prevailed that brandy was a more healthful beverage than any other spirituous liquid on account of its erroneously presumed purity. There was a time when physiologists believed they could calculate and express numerically the toxicity of an alcoholic beverage the amounts of aldehyde furfural some of the esters and some of the higher alcohols necessary to kill an animal having been determined and calculated into kilogramme-factors by Dajardin-Beaumetz Audig6, Rabuteau and others; thus the quantities expressed in grammes necessary to kill 1 kilogramme of animal amount for ethyl aldehyde to 1-00 gramme for acetic ether 4-00 grammes for ‘( higher alcohols ” 1-40 grammes and for furfural 0.24 gramme.Mastbaum calculating the toxicity for a comparatively pure refined wine alcohol, with the (‘ coefficient of impurity” of 175’7 and for a very impure brandy with the coefficient of 977.2 concluded that the impurities ” contained in 100 C.C. of these (“ anhydrous ”) beverages would respectively kill 63.7 and 342.0 grammes of animal. This is disregarding the toxicity of the ethyl alcohol itself. According to Dujardin-Beaumetz and AudigB this is 7.5 and 100 grammes of alcohol kill 12.9 kilogrammes. When this is allowed for the toxicity of the two samples in question comes to 12,963 and 13,242 respectively-that is to say the difference is altogether immaterial.I t is clear that the toxicity of an alcoholic liquor belongs to the alcohol and practically to nothing else. We cannot escape the logical conclusion which was arrived at some years ago by the Departmental Committee on ‘I Whisky,” that pure alcohol-that is to say, We now know that if anything brandy is an impure material THE ANALYST. 43 silent spirit-is if anything a more healthful beverage than the ordinary drinking spirits-aZZ barring the necessary Jlavoz~r. The importance which the consumer attaches to the origin of a spirit is infinitely less than that he attaches to the flavour. I am quite aware that I am littering an unpopular heresy but the clear outcome of recent analytical work with spirits proves up to the hilt that broadly the best-flavoured and the most valuable spirits are the least pure.Nevertheless it may be true that the cheapest spirits are the most noxious not because they are the most impure for the purest spirit (silent spirit) is the cheapest of all but just because for a given sum of money a larger amount of poison-that is to say of alcohol-is obtainable in the one case than in the other. A gallon of “ silent spirit ’’ without the duty costs but a few pence and cognac brandy as many pounds. No wonder that a given money value of the former can prove a poison where the latter imparts but the flavour to a cup of coffee. The subject is surrounded by a nimbus of popular prejudice and it is comparatively easy to convince a magisterial bench that the vendor who supplies (‘ silent spirit,” which largely because it is foreign and cheap is credited with poisonous properties injures the health of the community.Nevertheless it is clearly against the spirit of our legis-lation to substitute one thing for another. If the health of the purchaser is not prejudiced it may be that his pocket is. Of few things however the ordinary person is more capable of forming a correct judgment than of his drink and we Public Analysts I fear can do but little at present to assist him in forming a judgment as regards derivation and quality. By the various prosecutions we have not only not assisted the purchaser but an effect quite contrary to that intended has been pro-duced.Just as certain regulations on the Continent have led to the appearance of a multitude of brandy-flavouring preparations the analyses of scores of which have been published in Koenig’s book so a brandy-ether industry has commenced to flourish in England. I have it on the authority of one of the manufacturers himself. I also know from a large ‘( brandy ’’ merchant that so-called very cheap brandy is now sold with a guaranteed content of what they call ‘‘ 80 per cent.” of ethers. In view of the fact6 set forth above it behoves Public Analysts to be cautious. It is their function to protect the public from fraud and to insure that the purchaser gets what he has a right to expect; but they must not go one tittle outside their knowledge of the facts.As scientific advisers there must on no account be any pretence that something can be done by analysis which is beyond the chemist’s knowledge There is it seems to me some danger that zeal in the public interest may lead some analysts to take that course. The names of articles of food and drink do not necessarily apply now to the selfsame substances as formerly. Beer was undoubtedly for a long time a malt and hop beverage ; whisky equally without doubt was a product of fermented malt-wort. They are not so now. The product may be the same or may be deemed by the public to be the same but the raw material has changed. The time may come (I personally rather think that it will come) when brandy will mean only a brandy-flavoured alcohol no matter from what source that alcohol is derived just as the term “ whisky ” at the present time is legitimately applied to a whisky-flavoured fluid not necessarily made from malt.Public Analysts by premature action based upon imperfect knowledge are much more likely to hasten the advent of that time than to prevent it. Everything turns upon the latter 44 THE ANALYST. DISCUSSION. The PRESIDENT (Mr. Fairley) said he was sure they were all indebted to Mr. Hehner whether they agreed with the views he had formulated or not for the great care and trouble which he had taken in preparing this paper. He himself had not had any samples of brandy submitted to him for this purpose and formerly he had tested the alcoholic strength and general characters of the distillate and the amount and nature of the fixed residue.As he had not had any samples he thought be might claim to take up a more neutral position and to speak somewhat as an out-sider. The Sale of Food and Drugs Act spoke of ‘‘ the nature and quality of substances demanded ” and of prejudice to the purchaser,” which meant that the purchaser should get what he reasonably expected to get. The ordinary purchaser had little knowledge of many of the articles he consumed. His idea might be founded on prejudice or on bygone experience but he (the President) thought that when all was said and done whether or not they adopted the views of Mr. Hehner the purchaser no matter how ignorant he might be had some right to get what he expected to get. Mr. Hehner admitted that the time was when all brandy sold in this country was cognac brandy.With the extension of commerce and of the cultivation of the grape in various countries and with the improvements in the methods of fermentation and distillation came a variety of liquids whose status had now to be decided. Some of these points were defined in Circular No. 18 recently issued by the United States Department of Agriculture drawn up by Dr. H. W. Wiley the Chief of the Bureau of Chemistry of the Department. Brandy (potable brandy) is the distillate from wine properly aged by storage in wood to eliminate the greater part of the fusel oils etc. which may be present. Brandy should not contain less than 45 nor more than 55 volume per cent. of alcohol and not more than 0-25 per cent. of total solids (extract). The content of fusel oils should not exceed 0.25 per cent.Brandy should not be mixed with alcohol from any other source than that of distilled wine. The distillate from the lees pomace and refuse of the winery is not entitled to bear the term ‘‘ brandy” in the potable sense. Cognac ” is only admitted as a name in the case of brandies made in Cognac from wines grown and manufactured there. No artificial colour other than that derived from the wood in which they are aged is admitted in brandies. One question was, had the Public Analysts who had brought this matter forward exceeded the reason-able limits of their duty? He knew of cases where very considerable pressure had been brought to bear on certain Public Analysts to go into this matter. He had very great sympathy with such cases and with those who were honestly trying to do their duty in dealing with the matter.Only by continuous effort could improvement be attained as was well shown in the analysis of butter and even of milk. Mr. FISHER said it had become necessary to form an opinion and take a line in this matter and the responsibility was on him as on others of saying whether certain samples purchased under the Food and Drugs Acts were to be accepted as brandy. Some samples containing a very low proportion of acids ethers etc. were alcohol slightly coloured and flavoured differing entirely from cognac and had no title to be called brandy. Others had the flavour and odour of brandy but showed a deficiency in certaio constituents. Such samples were probably mixtures or blend THE ANALYST.45 of cognac with rectified spirit which might have been made from grain beetroot or other material and if the mixture could be proved they were not genuine brandy. It could not be maintained that a grape brandy might be mixed with whisky or gin (if that were possible apart from the flavour) and the blend sold as brandy. H e must admit as Mr. Hehner had stated that it was not always possible to detect the origin of the alcohol when blended in the brandy; yet when alcohol had been produced by rectification from grape spirit it was a debatable point whether it became brandy by being mixed with another proportion of actual grape-brandy. He did not however believe that in nine-tenths of mixtures met with the alcohol was exclusively derived from wine. They were in fact compounded partly of what everybody would regard as brandy the other spirit being what nobody would admit was brandy.Mr. Hehner’s remarks indicated the need for careful examination of these cases and assertions must not be made which could not be substantiated. He did not regard this as a question of the differences in composition shown by the varieties of brandy made in Algiers Greece Spain or Australia. Each had, of course its own characters. He had given his opinion on samples which were afterwards admitted to be mixtures and he had examined samples which were labelled and sold as mixtures. With reasonable care and precaution he thought it possible to certify that a sample was genuine grape brandy or that it was a blend of the kind described. Mr.A. H. M. MUTER thought that it would be a great pity if the Society of Public Analysts came to the conclusion that they were unable to deal with this question. He thought it would be far better that an effort should be made and a, standard fixed as had been done in the case of milk. Mr. GORDON-SALAMON said that they must start first of all with the question which was the subject of the paper namely What is brandy? He thought the fact had to be accepted that the public regarded brandy as spirit derived from the grape and in giving evidence he should certainly support that view and no other. If he were correct in assuming that position then the question for the analyst to deter-mine was whether by analytical methods he could say ‘‘ Aye” or “ Nay,” is the public getting that article? Arising out of it was the further question-Does the present state of our knowledge permit us to come to a definite and reliable decision in respect of such a question? With all respect to the President he (Mr.Salamon) did not agree with the view expressed which in effect said ‘‘ Do not let US be dis-couraged. But meanwhile vendors were being prosecuted and evidence was being given by public analysts to the effect that such and such samples were adulterated with spirit not derived from the grape when at that meeting members were expressing grave doubts as to their being justified in making such a statement. In his opinion that was a position which did not reflect credit on the Society and until they were provided with some definite and proper method of analysis (which was approved by the profes-sion as a whole) they ought to be extremely careful in making statements upon oath before magistrates who would naturally look to them for guidance.On the other hand, one had to examine into the origin of this question. Mr. Hehner had very properly mentioned that it was due to the scarcity of brandy during the phylloxera ravages, and those who had investigated the manufacture of brandy as he (Mr. Salamon) might If we have not yet got to perfection of knowledge we shall later. 46 THE ANALYST. claim to have done in some at least of the countries of its manufacture knew that adulteration with grain spirit was very largely practised. He knew as a matter of fact that very large quantities of grain spirit had in the past been employed for the adulteration of brandy.He thought the practice was reprehensible and should if possible be stopped. Therefore he was one of the first to admit as the result of his own personal knowledge that brandy was subject to adulteration with grain spirit, and that the public very often did not get what they demanded in the shape of brandy. But that being admitted the next question was Could it be determined by analysis whether or no such addition had been made? Now what was the condition of the grain spirit as usually employed ? It was nearlyralways pure rectified spirit-as pure a spirit as could be found-and purchasers were extremely careful in their choice of such spirit. Assuming also that brandy was to be derived from the grape, was it justifiable to add distilled grape spirit to that brandy or must brandy be abso-lutely the untreated product of distillation ? Was it allowable to add spirit derived from the grape in the pure state at a later stage? In answering that question one must not forget that it was the common practice of the French brandy manufacturer to add pure spirit a t a later stage and to the bulk of the brandy sent from France pure spirit was frequently added and often in very considerable quantity.Therefore in seekiug to determine the origin of the spirit and the termsof its purity could an analyst say “Aye ” or “ Nay,” as to whether that spirit-assuming it to be rectified spirit-had been derived from the grape or from grain or from any other source ? Mr. Fisher had clearly answered that question and he (Mr.Salamon) held exactly the same view. It was absolutely impossible to make such an assertion. If that were the view of that meeting if that were the view of public analysts as a whole (and he did not see how they were to come to any other conclusion) what became of the whole ques-tion? Assuming a spirit-a brandy-containing 150 parts of esters per 100,000 of absolute alcohol were in the course of manufacture diluted down with rectified spirit until the esters were below the stupid standard of 80 by perhaps 5 who could say whether that had been legitimately brought about by the addition of pure grape spirit or whether it was due to the addition of grain spirit ? And if that could not be deter-mined how could it be said whether the brandy had or had not been derived from the grape.If one denied that issue one was thrown back upon the one which did not obtain in practice-namely that no addition must be made to the brandy after distillation. The articles published in the Lancet if he might venture to say so did not reflect credit on the leading medical journal of this country because the expert who made the investigation competent as he was in many respects had confined his visit to Cognac and the report of the so-called Commission favoured the impression that it dealt with the whole question of brandy upon a broad basis. He (Mr. Salamon) did not think the expert knew of the existence in France of many thousands of bozdleurs de cru small farmers who were permitted by special legislation to make brandy from their own cultivated grapes if they so desired.They were allowed to distil the spirit from their grapes instead of having to put an inferior wine upon the market. That permit had been inaugurated by the Government. Such brandies were sold and many of them went into the Cognac district itself and did so to this day although the law had been altered in respect of their production. On analysis such brandies, having been distilled not in pot stills but in nearly all cases by various modification THE ANALYST 47 of the patent still showed a great range of composition which was absolutely different from the composition of pot-still brandy as it was made in Cognac. Yet those brandies were genuine spirits derived from the grape. Spanish Algerian and Australian brandies were absolutely in the same category and only a relatively small proportion of the total brandy produced came from Cognac itself.Conse-quently it was unfair to set up a standard even assuming it could be supported by analysis which only applied to one portion of the brandy-producing area and that by no means the largest. Supposing however this standard were accepted would it not result in opening the door to sophistication? What easier than to construct a brandy that should answer the standard requirements of the magistrate-to make it up to contain the requisite proportions of ethers furfurol aldehydes etc.-and then send it out under the certificate of the public analysts of this country as a pure article? Mr. Hehner had said that a spirit might be judged by taste as well as or even better than by analysis; but he (Mr.Salamon) thought that they must be very careful in making such a statement. It might certainly be left to the taster to say whether the public would accept a brandy and how much they would pay for it ; but he (Mr. Salamon) did not think it could reasonably be left to him to say whether a brandy had been broken down with rectified potato grain or grape spirit. Mr. C. G. MOOR said that he spoke with a certain amount of trepidation because his views were to a large extent opposed to those of Mr. Hehner who had considerable advantage over him in point of knowledge of the literature of the subject. He thought everyone would agree that brandy had in the past at any rate possessed a con-siderable reputation as a medicine.I t was referred to in the British and many of the other present Pharmacopceias and was in some of the earlier editions also. I t was in the American Pharmacopceia which gave a long list of tests to provide against sophistication ; and it would also be found in the Austrian German and Hungarian Pharmacopceias in the Dutch Supplement and in the Swiss Pharmacopceia. The making up or ‘‘ faking ” of brandies by colouring silent spirit was certainly regarded as an adulteration in Canada. The Government Analyst there in one of his bulletins stated that the existence of this manufacture had long been known but that it was only recently that the various ethers etc. had been offered publicly for sale. Regarding the value of the ethers and their interpretation the view which he (Mr.Moor) held was that the 80 parts of ethers per 100,000 of alcohol was simply a working standard just as long ago 2.5 per cent. and then 2-75 per cent. and now 3 per cent. was a working standard for fat in milk. Even now it was perfectly well known that a great deal of milk was ‘‘ let down” to the 3 per cent. limit but never-theless it did provide against and formed a working basis for detecting the worst adulteration. I t was in this way that he thought they should do what they could in regard to brandy rather than follow what might rightly be described as a policy of despair. H e thought therefore that they must have some kind of standard and that the 80 parts of ethers per 100,000 might be used for the moment. H e ventured to think that in the case of brandy of any well-known make a sample manufactured before this agitation arose would contain over 100 parts of ethers per 100,000.I t was perfectly clear of course that ethers could be added to silent spirit suitably coloured and that such an article would pass the suggested standard as regards ethers; but it was quite obvious that samples containin 48 THE ANALYST. as little as 20 30 or 50 parts of ethers per 100,000 were not genuine brandy. He regarded brandy as the spirit derived from the grape in a pot-still simply because that was the origin of brandy before modern methods were introduced. There was one condition however under which the proportion of ethers might fall below an arbitrary standard. When brandy was made from “sick77 wines it was customary he believed to throw away the first part of the distillate because it was nasty and could not be mixed with the rest and because the distillation being carried out in a country where there was no alcohol regulation it did not matter about a portion of the distillate being thrown away.About a month previously he had been permitted to rend a paper on this subject at a meeting of the Therapeutical Society at which were present several of the most prominent medical men of the day; and he had particularly invited an expression of opinion as to whether there was really any physiological action or advantage in a good genuine brandy or in a good wine or whisky apart from the alcohol present. He had been surprised to find that none of the medical men would specially advocate brandy or say that there was any advantage in having matured spirit.The question from the point of view of the Public Analyst seemed perfectly clear. The purchaser was entitled to be supplied with what he asked for and anyone whether educated or ignorant wanted in the case of brandy what he believed to be the genuine article, and not artificially coloured silent spirit. Mr. JOHN HERON said that probably an expert in spirits would be able to distinguish between wine-spirit and grain-spirit by some similar method to the one he had himself employed for many years for distinguishing between beet and cane sugar. There was a subtle something clinging to the refined rectified article which stamped it at once as to its origin. Mr. SALAMON Whether it is pure or mixed with brandy ? Mr.HERON said that the difficulty that arose in the case of a mixture was that the constituents or impurities of the brandy would (and indeed must) belong to the same order or qua1it.y as those contained in the grain-spirit so that it would grob-ably be a difficult thing to attempt; but just as in the case of sugars the presence of an admixture (though not its quantity) could be detected he should think it ought to be possible after some experience to tell whether grain-spirit had been added to brandy. He had hoped that at that meeting some understanding might be come to as to what ought to be the necessary constituents of brandy. However, anyone who had been experienced in the analysis of brandy and other spirits would, in the very handling of the liquid come to know instinctively whether a particular sample was genuine brandy or not.He did not think that a right judgment could be formed on the basis of one constituent only but by comparing the different constituents one with another a very fair opinion could be arrived at as to the quality of the brandy. Mr. J. B. P. HARRISON said that the question of the sale of “British brandy” was an interesting one. Some Public Analysts held that there should be no such substance as ‘‘ British brandy,” as the term brandy ” in this relation was a mis-leading one ; and as the chief consumers of this kind of spirit were not sufficiently educated to distinguish between it and actual brandy the question was whether the purchaser knew what he was really receiving for the price he paid.He was als THE ANALYST. 49 of opinion that so long as the Excise recognised the sale of spirit in the guise of ‘( British brandy ’’ as a legitimate source of revenue there wouPd always be confusion as to what was really genuine brandy. Dr. SCHIDROWITZ said that he felt some little dificulty in speaking on this question from a purely analytical point of view because regarded in that light it resolved itself into a series of metaphysical speculations. If he were to ask himself, -What is brandy from an analytical point of view ?-he should reply that he did not know ; and he thought they were all in that position. He did not quite agree with Mr. Hehner about the literature of this subject. He thought that the literature on the subject of brandy upon which one could actually pin any faith was very small indeed ; and he did not agree that it was an impossible matter to practically substantiate the genuine character of a spirit.So far it had certainly not been done and whether one regarded the amalyses of Girard and Cuniasse of Mastbaum or of any of the other observers mentioned none of those analyses as far as he knew represented samples taken at the still-head. The grape of course could not be traced all through its growth up to the time when it was pressed and the brandy made from it but there were practical conditions-it was not necessary to make a special plea in any direction -under which samples might be taken so as to enable it to be shown within what limits the different qualities and types of brandy did vary.That had not been done, and he must say that until it had been the industry and trade concerned had them-selves largely to blame for the position in which they now are. He did not quite agree with Mr. Hehner’s classification of the by-products. His view was that in addition to the substances mentioned by Mr. Hehner there were many others about which generally speaking little is at present known. I n saying this he was not speaking merely as a matter of speculation but from various facts which he halt observed and which led him to say that there certainly were such substances. Another question was-What is brandy looking at it from the point of view of the manufacturer and not from the point of view of the analyst? After all the chemist should not consider himself merely as a person who put things into a test-tube and took them out again but he could be and was an aid to great industries and trades ; and therefore he thought that this matter should be looked at from the point of view of the industrialist also.If it were said that brandy was anything distilled from the grape whatever the degree of rectification he would put this case Supposing grape spirit to be rectified to the point of absolute alcohol and to be coloured with burnt sugar bottled and sold-Mr. CHAPNAN People would not drink it. Dr. SCHIDROWITZ continuing said that the question arose-Was such an article brandy or not? The purchaser said he did not think it was brandy ; the analyst expressed an opinion right or wrong; but broadly speaking they were all agreed that such an article was not brandy H e was not going to express any opinion as to the type of still that should be used or as to the degree of rectification that should take place because the matter regarded from a purely scientific point of view was in its infancy.At the same time he thought it a mistake to go to extremes in either direction. With regard to the toxicity of the higher alcohols he might mention that the kilogramme factor for the alcohols in general according to Dujardin-Beaumetz varied from about 6 for ethylic Where then was the limit to be set THE ANALYST. alcohol to 1.5 for amylic alcohol. He must say that he was strongly opposed to judging any fermented or distilled liquid on a single analytical figure. He did not say that in years to come it might not be possible in many cases to form an opinion by purely analytical means as to the character of a spirit but he ventured to think that it would never be possible to do so on the strength of a single analytical figure.The case of wine analysis might be instanced. Standards had been set up by the German Government on the strength of many thousands of analyses and yet since those standards had been set up cases had occurred of genuine wines which were entirely outside the limits. He had met with German white wines which he knew to be absolutely genuine but which by the official methods showed no tartaric acid at all. Some white wines again contained about twice as much glycerin as white wines of a similar class usually contained the high content of glycerin being perfectly characteristic of the particular wine in question.Anyone relying on a single analytical factor might find himself in the position with a sample yielding abnormal figures of that kind of causing a prosecution when the article was perfectly genuine. He (Dr. Schidrowitz) thought that nothing further was needed to demonstrate the absurdity of proceeding in that way. He had seen many certificates in which samples were stated to be genuine brandy on the strength of the analytical figures. He had not been studying this matter for the last few months only but had been working on spirits for a number of years and would never give an opinion as to the genuineness of a spirit on analytical figures alone though it might in some cases be possible to say that it was not genuine.But the seme of taste could be so trained as to work in association with analysis and then very often the chemist could do something useful; and even at the present time he could do a great deal if he worked in conjunction with an expert taster. Moreover he could assist the manu-facturer in his processes of fermentation distillation etc. and he could assist the trade with regard to blending fining and various other questions. Finally the chemist could act as a policeman but he did not think the chemist should confine himself to that r61e entirely. If an article was not genuine they were all agreed that speedy steps should be taken though what those steps should be was another matter. R e must demur to the statement in the American circular which the President had quoted that brandy should ‘‘ be properly aged in order to remove fusel oil,” because, whatever it was that disappeared in the maturation of spirits it was in his opinion, practically certain that it was not the higher alcohols.In his own experience he found that old spirits contained on the whole rather more fusel oil than new spirits and theoretically regarded there was no reason why they should not. This statement however with regard to fusel oil had been handed down from generation to generation until at last it had come to be believed. With regard to the medical opinions which had been given from time to time with regard to brandy, he had been trying to discover the record of any scientific physiological experiments on genuine brandy whisky or any other spirit side by side with plain alcohol but there were no such experiments; and even if a medisal man recommended genuine brandy he did not know what would happen if some other spirit were tried.H e (Dr. Schidrowitz) agreed that the effect produced was mainly due to the alcohol and to nothing else; but he held the view that where special and beneficial physio-logical effects which could not wholly be credited to the ethylic alcohol had bee THE ANALYST+ 51 produced these were to be ascribed rather to the age of the spirit than to its original character. Dr. THORNE said that the fact rather seemed to have been lost sight of in the course of the discussion that a standard had been more or less officially put forward, and that the number-80 parts of ethers per 100,000 of spirit-had become more or less fixed in people’s minds.It seemed to him that as a Society of Public Analysts, they ought carefully to consider whether they were justified in letting that stand for present use. Whether they might eventually come to the conclusion that brandies when properly made might be above such and such a standard was a point which might develop as time went o n ; but he thought it an undoubted fact that at the present time really pure brandies did not all contain ethers up to the standard of 80 parts per 100,000 and that therefore to make that one point an absolute standard was an injustice on the one hand and a great danger on the other. Although he was not personally connected either with public analysis or with the spirit trade he happened to know that at that moment there was a large consign-ment of real Cognac spirit which had been in England for something like ten years or more and which had been bought at a high price with the best expert authentication, but which on analysis showed only67 parts of ethers per 100,000.That was a spirit which had cost originally certainly seven or eight times the price of many spirits that would be passed on the standard of 80 and was really a very fine Cognac. The danger on the other hand that imitation brandies might be made up was of course, one to be fought against; but there was a very great danger that if this one particular standard were fixed at a point which was higher than was fair really good and sound brandy would be condemned and there would be a tendency to add small quantities of ethers not for the purpose of making really sophisticated brandy, but in order to bring real brandy into a safe position with regard to police-court proceedings.That was undoubtedly a serious danger and he thought therefore, that the Society ought to go so far as to take the position that at the present time the ether standard of 80 parts per 100,000 was not justifiable and ought not to be maintained as an absolute legal test of good brandy. &fr. BEVAN said that he could confirm what Dr. Thorne had said having had occasion to examine a sample of 1848 brandy which showed only 57 parts per 100,000 of ethers. Mr. CRIBB said that with regard to the adoption of the standard of 80 parts per 100,000 for the ethers that nobody intended that to be taken as a rigid standard, but simply as a basis for calculation.Nobody would dream of prosecuting for 67, for instance or any figure nearly approaching 80. In all the cases that had been brought into court the ether figures had been very much lower-as far as we knew, never more than 40. I n those cases in which he was concerned they were very much lower-some lower even than those yielded by samples sold as L L British brandy.” It must be borne in mind that 80 was very far from being the average figure. The average proportion of ethers shown in the analyses by Girard and Cuniasse and also by Vasey was something like 136 and if Marc brandies were included it was about 180. Mr. HEHNER That was for cognac.Mr. CRIBB That in France is the same thing as brandy in England 52 THE ANALYST. Mr. HEHNER May I say that (‘ cognac ” in French and in English is “ cognac ” ; “ brandy ” in French is simply ‘‘ eau de vie ” ? Mr. CRIBB said that he had been in a great many hotels in France and had never been asked to have anything but cognac. eau de vie ” was never once used in his hearing and it was notorious and openly admitted that the stuff offered as I‘ cognac ” for use with coffee might be anything. He was quite sure that in France the word “ cognac ” was used in the loosest possible manner. If the average was as high as 136 it was quite obvious that the number of cases in which genuine brandy came much below 80 must be very few indeed and as a matter of fact amongst all the analyses of Girard and Cuniasse and of Vasey there was only one.He should like to ask Mr. Hehner if he could tell him the number in the papers by Windisch and others to which he had referred. Mr. SALAMON thought it might interest the meeting to hear that a couple of weeks previously he had had from one of the largest importers of brandy into this country two samples which he had to report upon as being below 80 in ethers and therefore not capable of passing the magisterial standard. His clients had thereupon sent him a letter accompanied by a report from the French Government authorities, stating that those brandies (as a special matter) had been prepared under Govern-ment supervision. A certificate of origin and a certificate of purity were also produced, in which it was declared that both brandies were pure grape brandy.Mr. CIRBB said that he did not dispute for a moment that samples did come below 80 but the number was very few indeed. Mr. HEHNER said that there were scores of cases. In a report made by the Lancet commissioner himself three samples of Algerian brandy were shown to contain respectively 62.73 47-6 and 55.3 parts per 100,000 of ethers; and the report con-tinued “ The figures coincide with those obtained with genuine though somewhat young brandies.” These Algerian brandies consisted of spirit derived entirely from the grape. Thus the same authority that had fixed the standard of 80 had also fixed the standard of 47. Mr. CRIBB said he should like to mention that Algerian and Spanish and most other brandies grown out of France had a very different flavour from that of French brandy and would hardly be recognised as brandy by regular drinkers of that spirit.The term Mr. SALAMON said that the brandies he had spoken of came from France. Dr. SCHIDROWITZ remarked that the ‘( certificate of origin ” applied to anything, whether absolute alcohol or brandy that was distilled from the grape. Mr. CRIBB said that a good deal had been heard about rectified grape spirit but he had never seen any published analyses 01 it and should be pleased if Mr. Hehner could refer him to any. He had been himself trying to obtain samples of it but had only succeeded in getting one which contained 67 parts of ethers per lOG,000. Possibly that was abnormal; if not it showed that the presence in a brandy of rectified spirit derived from the grape would not seriously affect the validity of the ether standard if judiciously employed.With regard to Mr. Hehner’s remarks to the effect that the value of brandy and of all spirits consisted entirely in their flavour, and that no value in the present state of knowledge could be attached to any one of the analytical constituents it seemed to him (Mr Cribb) that if they were to go merely by flavour any concoction whatever as long as it tasted right would pas THE ANALYST. 53 muster no matter how it was made. That however was entirely contrary to the spirit in which they had hitherto carried out the requirements of the Sale of Food and Drugs Act. With regard to the article in the Moniteur Oficiel of course every-thing depended upon what one accepted as being genuine brandy and it seemed to him that even in France the question must be a very difficult one unless the manu-facture could be followed all through.One difficulty arose from the use there of portable stills which were carried about the country to anyone who wanted to employ them. It was quite obvious that brandy made in that way might be subject to all sorts of admixture for there could be very little control over it. He did not know how far an Inland Revenue officer went round with the stills but from what he had heard he did not think that that was done. I t had been remarked that the laying down of a standard had a most unfortunate effect in opening up the way for adultera-tion ; but surely the absence of any standard at all would do this to a much greater extent.With regard to the question of tasting Mr. Hehner and Dr. Schidrowitz were apparently in conflict. In all the cases that had been at all fought the evidence of the taster had been called in and had confirmed the opinion of the Analyst. He did not see how anybody at the present time could say that a sample was genuine, but in some cases it was possible to say that one was adulterated and with greater confidence of course if the analytical evidence were supported by that of the palate. Mr. CHAPMAN thought that this question emphasized in a very marked degree the necessity for the establishment of a Consultative Board or Court of Reference such as had been recommended by a Royal Commission and by a Select Committee and more especially a Board constituted in the manner indicated by Dr.Thorpe in the Minority Memorandnm which he had signed in connection with the Royal Com-mission on Arsenical Poisoning-viz. a body including not only scientific men but also manufacturers and others possessing special technical knowledge. Not only was it unfair to the Public Analyst to compel him as is very often the case to set up standards for himself but such a proceeding was extremely undesirable from every point of view ; and he hoped that before long this function would devolve upon a Government Department possessing the necessary facilities for obtaining such scientific and commercial information as might be necessary for the purpose. Mr. Hehner had in his opening remarks made a very clear and lucid statement ; and he (Mr.Chapman) cordially agreed with a great deal that Mr. Hehner had said. He would however like to take the opportunity of expressing his dissent from the view which had been put forward in some quarters that brandy might practically consist of anything which looked and tasted like brandy and which was analytically indistinguishable from that spirit. He (Mr. Chapman) thought that was a position which many of them would hesitate to take up for it was one which if carried to its logical conclusion would lead to such assertions as that a mixture of glycerides similar to that occurring in butter and incapable of being distinguished from butter by chemical analysis might if it possessed the requisite flavour be sold as butter without prejudice to the purchaser.He felt that was an extremely dangerous position to adopt. The main point in connection with that meeting centred very largely in the answer to the question Were they in a position to make statements such as were being made and sworn to in courts of law in reference to samples o 54 THE ANALYST. brandy examined under a Criminal Act ? So far as he was able to judge he thought that the general feeling of that meeting was that they were not justified in making such statements. He thought there could be little doubt that the demand for ethers was very largely due to their supposed stimulating and medicinal effect. He was certainly not prepared to say that the ethers did not possess such valuable properties, but he did feel that it was an absurdity to demand that a spirit the great bulk of which was used as a beverage should conform to a certain analytical standard merely because EL certain small proportion was used for medicinal purposes.I t was for the Pharmacopceia Committee of the General Medical Council to see if they thought proper that brandy sold as a drug should conform to some required standard; but for the rest the purchaser must and would eventually be the judge as to whether what was supplied to him was good value or not. If it should become possible to distinguish analytically between grape spirit and that which was not grape spirit, well and good; but to insist that all brandy should conform to one analytical standard was about as absurd as it would be to demand that all clarets should conform to the analytical type of a Chiteau wine.Mr. Heron had raised an interest-ing point as to the possibility of distinguishing between alcohol from different sources. He (Mr. Chapman) believed it to be a fact that alcohol obtained from grain even when very highly rectified if added to wine could be readily detected by the trained palate whereas alcohol obtained from wine was capable on the other hand-to use a wine-merchant’s expression-of “ marrying ” or blending perfectly. Mr. CRIBB in reference to what Mr. Chapman had said as to the ability of the taster to distinguish between grain spirit and grape spirit said that he knew of a large London buyer of Spanish wines which had to be fortified by the addition of spirit who had inserted in his contracts with the foreign producers a special clause providing that no grain spirit should be added ; and he professed to be able to tell a t once by the taste whether grain spirit or grape spirit had been added.Mr. HEHNER in reply said that he considered it to be entirely within the right of the State or its representatives to Bay as guardians of the public “ We will only permit a thing to be called brandy if it conforms with certain arbitrary regulations which we the Government have a right to lay down.” The State could exclude if it chose anything although it might be legitimately made from a particular source, and could say that it should not-in England at any rate-be called brandy. The State could say if it chose ‘‘ We insist upon nothing but a certain quantity of ethers.” But he (Mr.Hehner) thought that it was not the business of the analyst to do so. The analyst had absolutely no right to do so and only imposed upon the magisterial Bench by suggesting that he could do such a thing. There were he reaffirmed a very large number of analyses on record-well-authenticated analyses made by competent people-which showed this. He quite agreed that those analyses were not all made upon the same standard for it was notorious that the methods of deter-mination especially in the case of the higher alcohols gave widely varying results. But the figures obtained by each method were more or less comparable among them-selves and if that condition were accepted it might be said that there were many hundreds of analyses on record though if the matter were regarded in the strict, scientific sense the number of trustworthy analyses was very small.There were very many cases on record in which brandy fell as regards ethers below brandy o THE ANALYST. 55 authenticated origin and he agreed that this happened with much greater frequency in the case of brandies not of French origin. But these were not chemical curiosities, but articles of trade that were imported to the extent of tens of thousands of barrels, and when an article was once imported the public analyst at any rate had no means of ascertaining whether it came from one country or another. When all these things were taken into consideration it seemed to be absolutely absurd to judge by Cognac standards an article which was simply called ‘‘ brandy,” just as it would be absurd to judge all wines by the higher German standard or to use in any other case a measure which was not applicable.H e did not advocate a policy of despair but he did not want analysts to bolster themselves up with fairy tales and to say that which they did not at present know but which they might know at some future time. However far one went it would not be found that alcohol from whatever source was anything different from C,H,O. While however impurities attached to the alcohol, he fully believed that it would be possible more or less to distinguish by taste-not because the alcohol was different but because the impurities were still there. That was the sense in which he had spoken when he said that one alcohol was as good as another.He quite agreed that sugar from the beet and sugar from the cane could be distinguished even if highly refined by the traces of the mother liquors which they contained; but it was not suggested that cane-sugar was different from beet sugar. A trade expert was perEectly entitled to go into court and express his opinion which might be a perfectly correct one but he (Mr. Hehner) thought that an analyst had no right to make a statement which was based on taste. His function was to analyse the article and to judge it from the chemical and physical point of view. He (Mr. Hehner) fully agreed that the analyst was in very many cases quite right when having found that there was a deficiency of ethers he gave his opinion that the article was not ordinary brandy because undoubtedly very many artificial mixtures were made.Such mixtures were often sold as “ British brandy ” in the first instance and afterwards sold by the publican without the qualification ‘‘ British.” The analyst however could not possibly in such a case say for certain that the deficiency in ethers was due to any artificial addition; it might be due to natural causes and he (Mr. Hehner) did not think it was fair that they as public analysts should take upon themselves to make a definite accusation when the variation was just as likely to be due to other causes. If any-one had actually seen anything added he was of course at liberty to say so but that was a matter for the policeman rather than for the analyst. The question had been raised with regard to other articles-the case of foreign meat and English ineat for instance-and he could not see why the same principle which applied in that case should not be applied to brandy or whisky.It was not weakness to say that there was no scientific means of distinguishing; the harm was done by pretending to do that which could not be done. That change which had been experienced in all other departments of the spirit industry must he thought irre-sistibly come to be applied in time to brandy. He perfectly agreed with Mr. Fisher that nine-tenths of these deficient brandies were mixtures that had been artificially ‘‘ let down,” but he was perfectly convinced that there was not only no one single determination that would be of any assistance in distinguishing such mixtures but that no possible combination of the determinations now available would be of an 56 THE ANALYST.assistance either. There were undoubtedly genuine brandies which were high in ethers and low in higher alcohols and vice versd; and there were undoubtedly genuine brandies which were very high in aldehydes and low in higher alcohols. I n fact all possible combinations existed in undoubtedly genuine brandies. Why should they who knew really nothing officially about the preparation of brandy because it was not a British manufacture pretend to know more than those whose life business it was to watch the production? No Government could have been more interested than the French to keep the brandy industry a national one but they had failed and had acknowledged it.Their last Report which he had ventured to quote was to the effect that it was impossible to lay down any standard because the impurities varied from 15 to 1,200. If there were any Pharmacopceia which gave information as to how to ascertain whether its requirements were complied with he should be very pleased to see it. I t was very well to lay down certain laws and to say that brandy should be so-and-so; but the public analyst had to say whether it was so and the complaint against the British Pharmacopceia was just that it laid down a set of laws which no one could comply with or enforce because the analytical data were wanting. If a Pharmacopceia stated that for its purpose brandy should contain a certain quantity of ethers (200 parts per 100,000 if they liked) let it be so; but that surely, could not be a question of brandy for the public. His own feeling was very strong on the matter. He confessed that not very long ago he should have taken a dia-metrically opposite position and should have said that brandy must undoubtedly be made from wine. It might be that he was wrong in altering his view but he found that neither he nor anybody else in this or any other country had been able to do any better-that there was no means of distinguishing and that the more analyses that were added the wider the limits became. That might be called a policy of despair, but the real reason was that they could not fight against Nature. With regard to the question of asking the Government to fix a limit the Government had known for many years that adulterated brandy was imported but had never raised its voice. Blending had taken place openly and the public might have cried out but the Government had done nothing. Why public analysts should take upon themselves to do that which the Government had refused to do and which in the case of whisky, they had deliberately avowed themselves unable to do passed his comprehension

ISSN:0003-2654    

DOI:10.1039/AN9053000036

出版商:RSC    

年代:1905

数据来源: RSC

摘要:

THE ANALYST 57 ABSTRACTS OF PAPERS PUBLISHED IN OTHER JOURNALS. FOODS AND DRUGS ANALYSIS. Detection of Watered Milk by the Refractometer. A. E. Leaeh and H. C. Lythgoe. (Jozwn. Amer. Chem. Xoc. 1904 xxvi. 1195-1203.)-Numerous tabulated results are given of determinations of the refractions shown by the sera obtained from genuine and watered milks. The instrument employed was the Zeiss immersion-refractometer (ANALYST 1903 91) but the Abbe refractometer may also be used. In no case did the serum of a pure milk give a lower reading on the Zeiss instrument than 39.0 at 20" C. (103424 AbbB) figures from 40 to 44 being usually obtained. A milk serum giving a reading of 4240 when mixed with 10 per cent. of water gave a reading of 39-75 and with 20 per cent. of water 36.90 (see ANALYST, 1903 241).w. P. s. A Thickening material for Cream. F. Reiss. (Zeit. Untersuch. Nahi-. Genussmittel 1904 viii. 605-607.)-Attention is dpawn to a solution sold under the name of '' Grossin," which consists of a solution of calcium oxide (5.50 per cent.) and sugar (10.50 per cent.). The mixture is opalescent owing to the presence of a little calcium carbonate. It is intended to be added to thin or scalded creams to thicken them and at the same time to neutralize the acidity of the cream. w. P. s. Detection of Artificial Colouring Matters in Pastry. K. Dannenberg. (Zeit. Untersuch. Nahr. Genussmittel 1904 viii. 535-538.)-Wheat meal always yields some colouring matter when extracted with alcohol and which cannot be removed by previous extraction with ether.The author therefore proposes to use 25 per cent. alcohol as a solvent spirit of this strength dissolving neither the natural colouring substances of wheat nor oE eggs. Thirty grammes of the powdered pastry are treated with 50 C.C. of 25 per cent. alcohol and after shaking allowed to stand for six hours. If the alcoholic solution then be yellow added artificial colours are present in the sample. I n their absence the solution will be colourless or dirty gray. To prove the presence or absence of colours which are insoluble in alcohol but soluble in ether the sample is extracted several times with boiling absolute alcohol, and then treated with ether. Should the pastry not be quite discolourized by the alcohol but completely SO by the ether an ether-soluble dye is present.w. P. s. Characters of Indian Beeswax. D. Hooper. (Agricultural Ledger Calcutta, 1904 No. 7 ; through Pharnz. Journ. 1904 lxxiii. 505.)-The author furnishes in his paper a very complete account of the sources preparation and composition of British Indian beeswax. Derived from the three under-mentioned species of bees, the waxes aB separated from the combs are practically identical in composition, and are rarely adulterated. The wax differs from The chief source is Apis dorsata 58 THE ANALYST. European beeswax mainly in its lower acid value. available renders it a probable and valuable commercial source of supply. The large quantity of the wax The waxes have the following analytical characters : maximum mean maximum mean . minimum Melting-point "C.. . . Acid value . . Ester value . . t Iodine value . . . . Apis Dorsntn. 1 Apis h d i c a . 67 60 63.1 10.2 4-4 7-0 97.8 69 *5 894 9.9 4-4 6.7 64 62 63-2 8.8 5-0 6.8 95.9 84.0 89.6 9.2 5.3 7.4 Apis FZorea. 68 63 64.2 8.9 6.1 7.5 123.8 80.8 95.6 11.4 6.0 8.0 Some wax is also collected from the allied Dammar or Kota bees Melipona (Trigona) species. These very small stingless insects produced a sticky dark-coloured wax having a melting-point of 70.5" C. ; acid value 20.8 ; ester value 89.6 ; and iodine value 42.2. The product more nearly resembles the propolis of honey-bees than true wax from which it differs largely in physical and chemical characters. A. R. T. Determination of Added Mustard Hulls in Ground Mustard.A. E. Leach. (JOUY. Amel". Chenz. SOC. 1904 xxvi. 1209 1210.)-Whilst the higher grades of mustard flour are almost entirely deprived of hulls some are occasionally met with containing added hulls to an extent exceeding the amount of hulls in the whole seed. In the author's opinion this should be considered a form of adulteration. The main points of difference between hulls and seed substance are indicated chemically by such constants as the total nitrogen crude fibre and the copper-reducing matters by the diastase method. The following table in which the results are given on the dried and fat-free substance shows this in a summarized form : maximum minimum Total nitrogen per average Crude fibre per cent . . Reducing matter (as Mustard Flour.9.61 8-27 9-04 4.26 2.31 3.24 0.93 0.00 0.37 Mustard Hulls. 5 *oo 3.40 4.14 22.20 13-74 18-11 7.06 1.51 4.27 Whole Seed. 7 -73 6-00 7.09 10.33 7 -24 8.05 3.13 1.39 2.40 The following limits are suggested for ground mustard expressed on the dry, fat-free substance The reducing matter (as dextrose) should not exceed 2-5 per cent. THE ANALYST 59 the crude fibre should not exceed 5 per cent. and the total nitrogen should not be less than 8 per cent. As shown by the microscope the sample should be free from more than minute traces of starch and should not exhibit an excess of hulls over seed tissue. w. P. s. Composition of Orange Juice. K. Farnsteiner and W. Stuber. (Zeit. Untersuch.Nuhr. Genzusmittel 1904 viii. 603-605.)-The juices to which the follow-ing figures refer were pressed from the oranges after removing the skins spongy tissue and seeds from the latter. The press and vessels for receiving the juice con-sisted of wood no metal being present. Grammes per 100 C.C. Specific gravity at 15" C. . . 7 7 , after boiling Total solids dried two and a hslf hours in water-oven . . Total sugar after inversion (as invert Ash . . . . . Citric acid (anhydrous) . . sugar) . . . . Alkalinity of ash (c.c. of N acid) Nitrogen . . . . . + Phosphoric acid . . . Glycerol . . . . . . Alcohol . . . . Polarization in 200-millimetre tube, direct . . . . Polarization in 200-millimetre tube, after inversion . . . From Oranges of Unknown Origin.Fresh. 1.0429 1.0454 10-73 1.19 8.26 0-41 5-40 0.064 (0.38) -1.44:;~ --Fermented. 1.0084 1-0159 3-55 1.25 0.38 0.42 5.62 0.053 0.026 (0.61) 4.89 L -From Valencia Oranges. 1.0464 1.0466 1092 1.79 7.65 0.52 7.20 0.099 0.027 (0.34) - 0.11" - 3.16" -From Messina Oranges. 1.0451 1.0455 10.85 1-47 7 -86 0.50 6-40 0,075 0.042 (0.28) -+ 2.45" - 3.66" Determination of Mustard Oil in Mustard Seeds. w. P. s. Vuillemin. (Plzumz. Centralh. 1904 xlv. 384 ; through Xchimmel and Co.'s Repoyt October-November, 1904 59.)-The author proposes the following modification of K. Dieterich's method : Five grrtmmes of mustard seed are triturated as finely as possible with a little water, transferred to a round-bottomed flask of 200 C.C.capacity and 100 C.C. of water at a temperature of 20" to 30" C. added. The mixture is then allowed to stand in the closed flask for one hour with frequent agitation. After the addition of 20 C.C. of alcohol the flask is connected to a Liebig's condenser an Erlenmeyer flask of 200 C.C. capacity containing 30 C.C. of ammonia and 10 C.C. of alcohol being used as the receiver. To this is connected a second flask containing ammonia and alcohol, to avoid the possibility of lose. About half the contents of the distilling-flask are distilled over while the condenser-tube is immersed in the liquid in the receiver. * A small quantity of an alcoholic solution of salicylic acid had been added to this juice 60 THE ANALYST.When the distillation is at an end the condenser is rinsed with a little water and the distillate in the flask mixed with 3 to 4 C.C. of 10 per cent. silver nitrate solution, and heated on a water-bath until the silver sulphide precipitate is well deposited and the supernatant liquid is quite clear. The hot liquid is filtered on to a tared filter the precipitate washed with a little hot water then alcohol and ether and dried at looo C. until constant in weight. Any silver sulphide from the liquid in the second receiver must be added to the main quantity. The amount of silver sulphide obtained, multiplied by 8.602 indicates the percentage of mustard oil in the seeds when 5 grammes of the sample have been taken for the analysis. A. R. T. A New Adulterant of Ipecacuanha.C. Mannich and W. Brandt. (Joz~r17. Plzarm. Chim. [6] xx. 276 ; through Phaym. Journ. 1904 lxxiii. 705.)-The root of Heteropteris pauci$ora already mentioned by Peckolt of Rio as being used to adulterate ipecacuanha has been examined by the authors. Whilst the exterior appearance of this root closely resembles that of ipecacuanha its histological structure is markedly dijferent. It contains no starch or raphides of calcium oxalate, but shows cells containing a peculiar brown colouring matter which is coloured black by ferric chloride ; the structure of the woody tissue and of the more highly developed parenchyma also diEers from the corresponding parts of true ipecacuanha. I n place of starch there is present a carbohydrate soluble in water which after precipitation by alcohol from its aqueous solution and redissolving in water yields a clear syrup on evaporation.When purified by reprecipitation and solution the carbohyrate has the formula C,HloO,~H,O and [a] - 40. 98" ; it does not reduce Fehlings's solution, is precipitated by barium hydrate and yields lsevulose on hydrolysis. It is therefore allied to bodies of the inulin group and has been provisionally named heteropterin. Heteropteris root contains no alkaloid but yields a small amount of a crystalline non-glucosidal substance. w. P. s. Colorimetrie Valuation of Rhubarb. A. Tsehirch. (Pharnz. Centralb xlv., 496 ; through Phawn. JouTn. 1904 lxxiii. 428.)-The author's method consists in the hydrolysis of the anthraglucosides of rhubarb and the solubility of the resultant oxymethyl-anthraquinones in ether.Half a gramme of the finely powdered sample is boiled for fifteen minutes under a reflux condenser with 50 C.C. of dilute sulphuric acid (5 per cent.). The cooled liquid is directly extracted with successive quantities of ether until the solvent shows no colour on the addition of a trace of caustic potash. The mixed ethereal extracts are next evaporated when the process of heating with dilute sulphuric acid and the subsequent extractions with ether are repeated on the residue. After complete extraction of the acid liquid the ethereal extracts are mixed and shaken with successive quantities of caustic potash solution (5 per cent.), using 200 C.C. in all until the alkaline liquid is no longer coloured red.The solution is then diluted to exactly 500 c.c. and 100 C.C. of this liquid further diluted to 1 litre. 350 C.C. of this solution when diluted to 1 litre should show a distinct cherry-red coloration against a white background the tint being at least an deep as that of an alkaline solution of aloe-emodin of 1 part in a million (prepared by adding a trace of alkali to an aqueous solution of emodin of this strength). The above dilution corresponds to a yield of 2.8 per cent. of oxymethyl-anthraquinones from the rhubarb THE ANALYST. 61 Good samples of the drug should yield from 2.8 to 4.0 per cent. The use of distilled water throughout the process is necessary since the lime in tap-water precipitates the oxymet hyl-ant hraquinones. A. R. T. Detection of Resinous Adulterants in Storax.Ahrens and Hett. (Phaniz. Cepztralb. xlv. 571 ; through Pharm. Jounz. 1904 lxxiii. 547.)-The authors base a test for the purity of storax on the ready solubility of resinous adulterants in cold petroleum-ether genuine storax being only very slightly soluble. The storax is ground down in a mortar with sand and petroleum-ether and the solvent evaporated. I n the case of pure storax a thick fluid residue is obtained having an acid value of 40 to 55 and saponification value 180 to 197. I n the presence of foreign resinous matter the residue is resinous has a terebinthinous odour and shows an acid value of 116 to 121 and saponification value 172 to 178. A. R. T. Constituents of Matico Oil. H. Thorns. (Archiv. der Pharm. ccxlii. 328; through Pharnz.Journ. 1904 lxxiii. 428.)-A sample of Schimmel and Co.'s matico oil of specific gravity 1.1343 at 16" was found to contain a hydrocarbon solidifying at - 18" C. and boiling at 121" to 130" (13 m.m.) ; a small quantity of a phenolic ether, the brorno-derivative of which melts at 123" to 124" C.; and the two isomeric apiols the so-called "dill apiol" being present to a much larger extent than the " parsley apiol." The (6 matico-ether " of Fromm and van Emster is stated by the author to be chiefly a mixture of the two isomeric apiols while the maticoic acid of the same observers is a mixture of the two isomeric apiolic acids. Matico-camphor and asarone were absent. A. R. T. Constituents of Essential Oil of Acorus Calamus. H. Thoms and R. Beckstroem. (Berichte Pharrn.xxxviii. 3187 ; through P?~urm. Journ. 1904, lxxiii. 428.)-The authors find the oil of sweet flag to contain free normal heptylic and palmitic acids ; acetic and palmitic acids in the combined state ; eugenol ; asaryl aldehyde ; asarone ; and calameone (C15H2602) melting at 168" C. the crystalline body previously noted by Schimmel and Co. and by Soden and Rojahn. Asarone responds readily to the action of phosphoric and arsenic acids the solid polymer par-asarone (C12H1603)3 being produced with rise of temperature. Par-asarone forms a transparent vitreous mass at 173" melts at 203" and is readily soluble in most organic solvents. On evaporation solutions of par-asarone leave a glassy residue having a crystalline structure. A. R. T. Essential Oil of Ilex Paraguayensis. (Haensel's Report ; through Phurm. Journ. 1904 lxxiii. 453.)-The prepared twigs and leaves of this plant constitute the well-known Math or Paraguay tea The dried leaves of IZex Paraguuyensis yield 0.77 per cent. of a yellow oil having in a marked degree the odour of the plant. The oil which is solid at ordinary temperatures and melts at about 26.5" C., has the following analytical characters Specific gravity 0.8875 ; optical rotation for 100 millimetres + 3-73' at 20" C. ; acid value 61 ; saponification value 91. The oil has an acid reaction and is readily soluble in 96 per cent. but only sparingly in 80 per cent. alcohol. A. R. T

ISSN:0003-2654    

DOI:10.1039/AN9053000057

出版商:RSC    

年代:1905

数据来源: RSC

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62 THE ANALYST. ORGANIC ANALYSIS. Preservative for Stareh Indicator. Frank X. Moerk. (ATTber. Drzcggist, xlv., 144 ; through Pharnz. Jozmz., 1904, lxxiii., 453.)-The author has observed that if 2 C.C. of oil of cassia be dissolved, by shaking, in a litre of starch solution prepared in the usual manner the liquid is preserved indefinitely. This is a great advantage to those frequently using the indicator, and no objection has yet been found to the use of this preservative either in qualitative or quantitative work. A. R. T. Invertin in Bees’ Intestines. Axenfeld. (Centralb. fur Physiol ; through Pharm. JOZLY?~., 1904, lxxiii., 428.)-Invertin is secreted in considerable quantities by the intestines of the bee, as well as of dipterous, coleopterous, and lepidopterous insects. Thus honey consists mainly of invert-sugar, even when the bees are fed with cane-sugar.A. R. T. Volumetric Determination of Phenol. Frank X. Moerk. (Anzer. Druggist, xlv., 144 ; through Pharm. Jo.zmz., 1904, Ixxiii, 453.)-The author has noticed that, in the determination of phenol by conversion into tri-bromophenol, and titration of the excess of bromine after addition of potassium iodide with thiosulphate and starch as indicator, the sharpness of the end-reaction is interfered with by the precipitated tri-bromophenol. Moreover, in the case of some old phenol solutions a bluish colour is acquired by the precipitate, which is not decolorized by excess of thiosulphate solution. These difficulties may be obviated by the addition of a small quantity of chloroform, added when the greater part of the brown iodine colour has been discharged by the thiosulphate.The precipitated tri-bromophenol is thus dissolved in the chloroform, and the end-point may be more easily observed. A. R. T. Determination of Phenols in Essential Oils. (Schim?izeZ and C0.k Report, October-November, 1904, 129.) - The method described by S. B. Schryver (see ANALYST, 1900, xxv., 18), in which sodamide reacts with phenols with production of ammonia, is not applicable to the determination of the alcohols of essential oils. The results obtained by this method when applied to the alcohols are much too high, probably owing to the fact that the excess of sodamide produces more far-reaching changes in the alcohol molecule than in the case of phenols. Schryver found that the method could only be applied to those oils containing phenols, and free from ketones and aldehydes, and it is now apparent that the method is limited to those oils which are simply mixtures of phenols and terpenes.Thus the method gives good results in the cases of clove oil, pimenta oil, and artificial mixtures of phenols and terpenes. On the other hand, in oil of thyme, which contains the alcohols linalool and borneol in addit’ion, thymol cannot be determined by this process. A. R. T. Essential Oil of Nikkei. (Schivmzel and Co.’s Semi-Annual Report, 1904, ii,, 96.)-This oil is obtained from the leaves and young twigs of the Japanese cinna- mon or cassia bark-tree (Cin?zamomzm Zoureirii), growing in the hottest provinces of Japan. The yield of oil is about 0.2 per cent,, and the product has a bright yellowTHE ANALYST.63 colour and a pleasant odour of citral and cinnamon, Nikkei oil has a specific gravity of 09005 at 15" C., an optical rotation of -8.75" for 100 millimetres, an acid value of 3.0, and an ester value of 18-6. It is soluble in 2 to 2.5 volumes of 70 per cent. alcohol with opalescence, and forms a clear solution with an equal volume of alcohol of 80 per cent. strength. The oil contains 27 per cent. of aldehydes (chiefly citral), about 40 per cent. of linalool, and some cineol. No cinnamic aldehyde was present. This constituent was found by Shimoyama in an oil from the root-bark of C~?ZW.X- mmu7n Zoureirii, which oil had a greater density (0.982) than the present sample. A. R. T. West Indian Limette Oil.(Schimneel mzd Co.'s Report, October-November, 1904, 54.)-The composition of two authentic specimens of limette oil from Dominica is given in the following table : Hand-pressed. Distilled. Specific gravity ... ... 0,9008 0.8656 Optical rotation for 'i00 millirnetres + 36.3' + 46-6" Optical rotation of first 10 per cent. distilled ... ... ... ... +39-5" + 53.1" Acid number ... ... . . . 6.05 1-80 Ester number ... ... ... 29.55 4.05 Residue on evaporation, per cent. ... 17.8 3.16 Both oils are soluble in 4 to 4.5 volumes and more of 90 per cent. alcohol, with slight cloudiness in consequence of the separation of a paraffin. The expressed oil shows in dilute alcoholic solution a faint blue fluorescence, probably due to the presence of methyl anthranilate.The oil has a golden-yellow colour, and a refreshing odour resembling that of lemon oil. The distilled oil possesses an unpleasant odour, resembling turpentine or pine-tar oil. A. R. T. Composition of Cypress Oil. (SchimnzeZ and Co.'s Report, October-N ovember, 1904, 22.)-This oil has been submitted to a further extended examination, and some hitherto obscure points cleared up. The following figures show the characters of cypress oil from two sources : French Oil. Schinimel and Co. 's Distillate. Specific gravity ... ... ... 0.8916 0.8680 Optical rotation for 100 millirnetres ... + 16.5" + 26.5" Acid number ... ... ... ... 1.88 Ester number ... ... ... ... 19.53 5-31 Ester number after acetylation ... 48-48 10.25 Solubility in 90 per cent. alcohol ...1 : 2.5 1 : 5.5 - I n the high-boiling fractions of the oil the sesquiterpene laevo-cadinene is present. " Cypress-camphor " is an important constituent, and may be obtained from the oil by '' freezing." Purified cypress-camphor crystallizes in long needles, which melt at 86" to 87' C. It is a sesquiterpene alcohol of the formula C,,H,,O, and distils at 290" to 292O C. An intimate relationship between cypress-camphor and cedar-camphor (cedrol) has been generally assumed, and it has been found that the latter is the optically-64 THE ANALYST. active (dextro-rotatory) modification of the inactive cypress-camphor. By the action of formic acid cedar-camphor yields a hvo-rotatory, and cypress-camphor a, dextro- rotatory hydrocarbon, C,,H,,. A mixture of the two shows no depression of the melting-point, but melts uniformly at 86' to 87" C.The following is a list of the known constituents of cypress oil: Furfural; dextro-pinene ; dextro-camphene ; dextro-sylvestrene ; cymene ; a ketone ; sabinol (?) ; a terpene-alcohol (?) ; dextro-terpineol (melting-point 35" C.), probably as acetate ; valeric acid ; lavo-cadinene ; a sesquiterpene-alcohol ; cypress-camphor ; and a body with a laudanum-like odour. Cypress oil is having an extensive trial, with some success, as a curative agent in cases of whooping-cough. I n other respects the two camphors are identical. A. R. T. Essential Oils of the Monardae. (Schirnmel and CO.'s Semi-Amual Report, 1904, ii., 57, 58, 97.)--5. W. Brandel (Pharin. Review, 1904, xxii., 153) found the dried herb of Monayda citriodoi-a to yield 1 per cent.of a reddish oil having a specific gravity of 0.9437 at 20" C . The oil contained 65 per cent. of phenols, carvacrol and hydrothymoquinone being identified. About 1 per cent. of citral was present, and probably also some cymene. The half-dried herb of H. didymu yields 0.04 per cent. of a golden-yellow oil of pleasant aroniatic odour. I t has a specific gravity of 0.8786 at 15" C., an optical rotation of - 24.6" for 100 millimetres, and is soluble in 1.5 to 2 volumes of 70 per cent. alcohol. According to Brandel, the oil does not contain any appreciable amount of carvacrol or thymol. The thymoquinone, which, together with hydrothymoquinone, is present in the oil from M. jktulosa, has been shown by F. Rabak (Pharnz.Review, 1904, xxii., 190) to be produced by the action of an oxidizing ferment on the hydrothymoquinone. This soluble ferment may be isolated by bruising the fresh leaves in a mortar and stirring the product into a pulpy mass with water. The liquid on expression and filtration yields with alcohol a precipitate of the ferment. Rabak has shown that the oxydase reacts on the hydrothymoquinone with separation of dark-coloured crystals, which are gradually changed into thymoquinone. D. B. Swingle (Pharm. Review, 1904, xxii., 193) supposes the ferment to be identical with the P-katalase of Low (U.S. Dept. of Ayric. Report., No. 68, 1). The ferment is destroyed at a tem- perature of about 74" to 78" C. This solution deposits a paraffin on further dilution. A. R. T. Composition of Rose Oils.Jeancard and Satie. (BUZZ. SOC. Chinz. [3], xxxi., 934 ; through SchinmzeZ nizd Co.'s Report, October-November, 1904, 79.)-The authors find the following analytical characters for an oil obtained from rose-blossoms after removal of the petals (i.e., from the calyx, stamen, and pistil) : Specific gravity at 15" C., 0-8704 ; optical rotation for 100 rnillimetres, - 41'; solidifying point, +8" C. ; acid number, 6.12 ; ester number, 22.4. A stearoptene, consisting chiefly of a body melting at +14" C., is present to the extent of 51.1 per cent. In addition, the oil contains also 13.6 per cent. of citronellol, which is the only alcohol present. A. R. T.THE ANALYST. 65 Crude. Constants of Bulgarian Rose Oil. (Schimwzel and Co.'s Report, October- November, 1904, 81.)-The following revised limits of composition for this oil are now stated : Specific gravity at 30" C.(water at 15" = 1-000), 0-849 to 0.862, rarely 0.863 ; optical rotation for 100 millimetres, - 1.5" to - 3-0" ; refractive index at 25", 1.452 to 1.464 ; congealing point, + 19" to + 23.5" C. ; acid number, 0.5 to 3 ; ester number, 8 to 1 6 ; total alcohol (as geraniol), 06 to 74 per cent., exceptionally up to 76 per cent. ; citronellol, 26 to 37 per cent., generally 30 to 33 per cent. The citronellol is determined by formylating the oil, the mixture, in the proportion of 1 volume of oil to 2 volumes of 100 per cent. formic acid, being heated for one hour over a reflux condenser. The method is then carried out as in the acetylation of oils. A. R. T. Rectified. 1 Crude. I Rectified. Some New Essential Oils. (Haensel's Repoyt, July, 1904 ; through Pharnz. Journ., 1904, lxxiii., 548.)-Burdock root yields 0-18 per cent. of a brownish-yellow oil soluble in 80 per cent. alcohol, and having an acid reaction. The flowerless Conium herb gives about 0.08 per cent. of an acid, dark-brown oil of unpleasant odour. It deposits a stearoptene at low temperatures. Rectification with steam only yields 25 per cent. of distillate, the cooled residue being black and solidified. The brownish coloured rectified oil, which is soluble in 90 per cent. alcohol and acid in reaction, has nearly the same odour as the original oil, and contains free palmitic acid. Conium fruits yield only 0.018 per cent. of a blackish-brown oil of evil odour and neutral reaction. The other characters of these oils are shown in the following table : On rectification 51 per cent. distills as a greenish-yellow oil. 0-9695 at 25" 0.9502 at 15" 0.9310 at 20" 0.8949 +1*24O at 30" - 13.5 60 236.8 70 - - - - 34 - Specific gravity Optical rotation (for 100 mm.) j Acid value . .. Saponification ) value i 0,8313 - 2.16" -- - A. R. T.

ISSN:0003-2654    

DOI:10.1039/AN9053000062

出版商:RSC    

年代:1905

数据来源: RSC

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THE ANALYST. 65 INORGANIC ANALYSIS. On the Determination of Silver in Zinc and the Amount of Silver in Various Grades of Commercial Zinc. K. Friedrich. (Zeits. angew. Chem., xvii. , 1636.)-From 200 to 1,000 grammes of the granulated sample are treated with hydrochloric acid, preferably added in several portions, the zinc chloride obtained being poured off before the next lot of acid is added. As it has been found that, as soon as all the zinc has dissolved, the hydrochloric acid attacks the silver, the metallic residue is collected on a filter while some zinc is still present in it. It is then very carefully washed free from chloride, the presence of which would ca,uBe66 THE ANALYST, loss of silver in the subsequent operations, and, after ashing the filter, is run down with 7.5 to 15 grammes of assay lead and a little borax in a scorifier. The lead button obtained is cupelled, the silver weighed and examined as usual for gold.I n order to allow for the loss of silver which always takes place during scorifying and cupelling, a quantity of pure silver, approximately equal to that contained in the sample taken, is run down in a scorifier with the same quantities of lead and borax as are taken for the main assay, and under as nearly as possible the same conditions, the lead button obtained being then cupelled and the loss in weight of the silver determined. This loss usually varies from 2.5 to 5 per cent. of the silver. I n thirty-one samples of zinc examined, the quantity of silver present varied from 0-00011 to 0.00648 per cent. in the ordinary commercial grades, and from less than 0.000005 to 0*000014 per cent.in various kinds of ( ( pure ” zinc. Gold was present only in traces, if at all. The method used was shown to be reliable on a number of artificially-prepared zinc-silver alloys, some of which also contained the usual im- purities of commercial zinc. A. G. L. The Use of a Rotating Anode in the Electrolytic Estimation of Zinc. Leslie H. Ingham. (Journ. Anzer. Chem. SOC., xxvi., 1269.)-The author obtained good results in the electrolytic deposition of zinc from various solutions, using a platinum spiral revolving at the rate of 230 or 560 revolutions per minute as anode. The cathode consisted of a silvered dish, from which the zinc was removed a t the end of each experiment by dilute sulphuric acid (1 : 50).I t was found that, using an electrolyte containing sodium acetate, 0.5 gramme zinc would be completely deposited with the higher speed in fifteen minutes, using a current of 4 ampkres (for about 100 square centimetres) and 11 volts. With sodium hydroxide solutions 0.25 gramme zinc could be deposited in fifteen minutes, using 5 amperes and 6 volts. From sodium formate solutions slightly acid with formic acid, 0.25 gramme zinc were deposited in twenty minutes, using 5 amperes and 8 volts. Potassium cyanide solutions gave unsatisfactory results. Both the sodium acetate and formate methods were found to be especially applicable to the determination of zinc in zinc blende, the time required to complete the analysis on 0.5 graiiime of ore being only about two and a half hours.The iron was removed as basic acetate or formate, the precipitate being dissolved in acetic or formic acid and reprecipitated, and the mixed filtrates were then electro- lysed. The sodium hydroxide method could not well be used, but good results were obtained by precipitating the iron with ammonia in the presence of a large excess of ammonium chloride, and directly electrolysing the filtrate, using a current of 5 amperes and 5 volts. The anode was found not to lose in weight during these experiments. A. G. L. The Electrolytic Deposition of Metals which Decompose Water from Solutions of their Salts. A. Siemens. (Zeits. amrg. Chem., xc., 247.)-The author has made a number of experiments to see whether metals which decompose water could be obtained from aqueous solutions of their salts by electrolysis, by using a metal other than mercury to act as depolarizer at the cathode.He found that magnesium may be deposited together with nickel from solutions containingTHE ANALYST. 67 salts of both metals, provided the concentration of the magnesium is great. I n dilute solutions, especially in the presence of ammonium salts, on the other hand, nickel may be quantitatively separated from magnesium. Magnesium may be similarly deposited with cobalt, less easily with iron, and only in traces with zinc. Aluminium and the metals of the alkaline earth group cannot be deposited at ell in this way. The alkali metals may be deposited in small amounts together with nickel and tin, but not with iron or silver ; ammonium appears to be deposited together with silver, but not with iron or nickel.I n all these cases the metals in question are merely dissolved in the heavy metal, not combined with them. Using high current pressures, the metals of the alkali and alkaline earth groups may be reduced from solutions of their anhydrous salts in acetone; magnesium, aluminium, and beryllium cannot be obtained in this way. A. G. L. Electrolytic Separations Possible with a Rotating Anode. Donald S. Ashbrook. (Joz~rn. Amer. Clzem. SOC., xxvi., 1283.)-The author has used an anode r o t a t i q at a speed of 300 to 400 revolutions per minute to effect the separation of a number of metals electrolytically. The dilution in each case was 125 c.c., and the cathode surface 100 square centimetres.I t was found that in a sulphate solution containing 0.25 gramme of each metal and 1 C.C. of free sulphuric acid, copper could be very completely separated in ten minutes, using a current of 4 to 5 amperes and 1 to 4.8 volts, from iron, chromium, zinc, manganese, and uranium, but not from cobalt or nickel. I n a nitrate solution containing 1 C.C. of free nitric acid, and using a current of 3 amperes and 4 to 5 volts, the same quantity of copper could be com- pletely separated in twenty minutes from cadmium, arsenic, iron, chromium, uranium, manganese, and magnesium. From a solution containing 10 C.C. of phosphoric acid (specific gravity 1,085) and 50 C.C. of a 10 per cent. solution of Na,HP04, using a current of 5 amperes and 6 volts, copper could be completely separated in ten minutes from iron, chromium, zinc, and magnesium, but not from nickel or cobalt ; the deposit in each case contained a trace of phosphorus.I t was not found possible to separate copper from antimony in tartrate solution. I n a so,lution containing 25 C.C. of ammonia and 2.5 grammes of ammonium nitrate, using a current of 5 amperes and 7 volts, copper was completely separated in fifteen minutes from arsenic. With lead in nitric acid solution low results were always obtained for the copper. Using similar solutions, it was found possible to separate completely, in sulphuric acid solution, cad.miuns from aluininium, iron, magnesium, manganese, and nickel, but not from chromium, which gave low, or from cobalt and zinc, which gave high, values ; the current used was 5 amperes and 5 volts, the time being ten minutes.I n phos- phoric acid solution, using a current of 5 amperes and 7 volts, cadmium was com- pletely separated in ten minutes from aluminium, chromium, iron, magnesium, and manganese, but not from cobalt, nickel, or zinc. Silver can be quantitatively separated from aluminium, cadmium, chromium, cobalt, iron, lead, magnesium, manganese, nickel, and zinc, the current used being 3 amperes and 3% volts, and the time fifteen minutes. The deposits obtained, how- ever, do not adhere a t all well, and hence great care is required not to lose any silver in the washing. I t was not found possible to use a potassium cyanide electrolyte.68 THE ANALYST, Merczwy was successfully separated in nitric and sulphuric acid solution from The conditions are not aluminium and magnesium, but not from other metals.stated in this case. il. G. L. On the Preparation of Pure Sodium Hydroxide for Laboratories. F. W. Kuster. (Zeits. anorg. Chenz., xc., 474.)-A large flat dish of porcelain or glass is filled with water to a depth of several centimetres, and a wide shallow bottIe or other vessel of platinum, silver, or nickel placed in the centre. Above this, supported by a tripod, is placed a large funnel, closed a t the bottom, made from pure nickel gauze. Into this funnel are put several hundred grammes of sodium at a time, and a bell-jar, slightly smaller in diameter than the flat dish, is immediately inverted over the whole, so as to shut off the sodium from the air by means of the water in the dish.To prevent the bell-jar from making too tight a joint, a few pieces of glass rod should be put on the bottom of the dish, As the water inside the jar evaporates, the sodium will gradually deliquesce, and the caustic soda formed drop into the bottle in the form of a 40 per cent. solution. The water in the dish is replaced from time to time ; a little caustic soda may be added to it, more effectually to shut out carbon dioxide, but in practice this is not found necessary. The sodium hydroxide obtained in this way is free from the usual impurities of sodium, which are left behind in the gauze. As regards price, sodium hydroxide prepared in this way costs only about as much as the commercial Nickel bottles may be obtained from Krupp of Berndorf.I t should be stored in Iarge nickel bottles. purified by alcohol” product. A. G. L. Preparation of an Alcoholic Solution of Potassium Hydroxide which will remain Colourless. H. Thiele and R. Marc. (Zeit. ofentl. Chenz., 1904, x., 386, 387.)-The authors recommend the use of potassium sulphate and barium hydroxide for the preparation of this solution. solution, 43.5 grammes of pure potassium sulphate and 110-120 grammes of barium hydroxide are triturated in a platinum or china basin with 100 C.C. of water. The basin and its contents are weighed and then heated to boiling for fifteen minutes, with constant stirring. After cooling, water is added until the original weight is again obtained. The contents of the basin are now rinsed into a large flask with 800 C.C.of alcohol,* and another 100 C.C. of water added. From 3 to 4 C.C. of a saturated solution of potassium sulphate are now introduced; the mixture is well shaken and allowed to settle. A small quantity of the clear supernatant solution is tested with sulphuric acid to ascertain its freedom from barium hydroxide, and the whole is then drawn off. The solution will be of approximately the desired strength, and will remain clear and colourless for months. To make 1 litre of w. F. s, Note on a Reaction of Potassium Ferrocyanide. A. Gutbier. (Zeit. aizorg. Chew,., xli,, 61.)-If to an aqueous solution of potassium ferrocyanide an aqueous solution of phenylhydrazine hydrochloride is added no reaction takes place in the cold. On warming, however, a light brownish-red colour is produced, which on increasing the temperature, changes through a light-red to a dark-red colour, suddenly * From the context it appears that ordinary commercial alcohoI is intended.THE ANALYST.69 disappearing a t the same time that a yellowish-green precipitate is produced, and nitrogen and hydrocyanic acid are evolved. By means of steam distillation a dark oil of unknown composition may be separated from the liquid. A. G. L. The Determination of Iodide in the Presence of Bromide and Chloride. E. Thilo. (Chew. Zeit., 1904, xxvii., 866.)-The author finds that when silver nitrate solution is added to a mixture of chlorides, bromides, and iodides, precipitation occurs in three stages. When this is completely separated, silver bromide comes down, and finally the chloride.The exact point a t which the iodide is completely precipitated is fixed by placing a drop of the solution on a strip of filter-paper which has been immediately before dipped in palladium chloride solution. I n the presence of the smallest trace of iodide a dark brown stain is formed, and the end-point is sharp to at least 0.1 C.C. of & silver solution. Bromide is determined in a precisely similar manner, continuing the addition of silver until no stain is obtained by spotting on gold chloride paper ; or chromate can be added and silver solution run in until the colour change indicates complete precipitation of the bromide and chloride, when the silver chromate is dissolved by the addition of a little nitric acid, and the mixed chloride and bromide filtered in 8, Gooch crucible and weighed.The excess of silver in the filtrate is determined by titration with sulphocyanide, after reduction of the chromate by ferrous sulphate. From the weight of the mixed precipitate, and the amount of silver present, the proportions of silver chloride and bromide may be calculated. Silver iodide is first formed. H. A. T. A Method for the Determination of Chloric Acid. W. S. Hendrixson. (8mer. Chenz. Joum., xxxii., 242.)-The chloric acid is reduced to hydrogen chloride by means of metallic iron in fairly strong sulphuric acid solution a t room tempera- ture. When reduction is complete, the chloride formed is determined by Volhard's method, nitric acid being added to oxidize the ferrous salt. The method gives good results, and is applicable to bromates as well as chlorates.Any perchloric acid present remains unreduced, and conse- quently does not interfere. The reaction requires about one hour. A. G. I;. The Electrolytic Determination of Nitric Acid with a Rotating Anode. Leslie Howard Ingham. (Jozmz. Anzer. Chem. Soc., xxvi., 1851.)-The author reduces the nitric acid to ammonia by electrolysing the solution in presence of copper sulphate ; a known amount of sulphuric acid being added, and the copper sulphate containing a known amount of acid, the quantity of ammonia formed is determined by titration. The conditions found to give the best results are as follows : 0.5 gramme of potassium nitrate is dissolved in water, 25 C.C. of standard sulphuric acid and 25 C.C.of copper sulphate solution, containing 0.2533 gramme of copper, are added ; the total volume is made up to 125 c.c., and a current of 4 amperes is passed through for thirty minutes, the voltage a t the outset being 10 and at the end 17 volts. Apparently the speed of the rotating anode is 230 revolutions per minute. At the end of the operation the liquid is titrated with standard ammonia, using litmus or methyl orange as indicator. In ten determinations made in this way the percentage70 THE ANALYST. of nitrogen found varied from 13.79 to 13.94, with a mean of 13.865, the theoretical value being 13.86 per cent. A. G. L. Analysis of Liquid Carbon Dioxide. 0. Wentzki. (Zeit. o f f e d . Chent., 1904, x., 385, 386.)-It has recently been shown by Woy (ANALYST, this vol., p.323) that the first portion of carbon dioxide drawn from an upright full cylinder of the liquid contains less air than the immediately succeeding portions, and that the quantity of air then gradually diminishes until pure carbon dioxide is obtained. The author considers that these results are simply due to the temperature of the contents of the cylinder. At temperatures below 2 2 O C. a certain amount of gaseous carbon dioxide is always present in the cylinder, and this contains considerably more air than the liquid portion. At 25' C., however, an ordinary full cylinder is completely filled with liquid carbon dioxide, and a portion, on being withdrawn, gives the average percen- tage of air in the whole. The withdrawal diminishes the temperature and the pressure, and some of the liquid is consequently converted into gas, in which the air present concentrates.A second sample taken from the cylinder will therefore contain more air than the first sample. w. P. s. The Determination of the Oxygen Absorption of Waters containing Large Amounts of Chlorides. Ruppin. (Zeit. Undersuch. Nahr. uizd Gerzussmittel, 1904, viii., 418.)-In the determination of the reducing power of waters towards permanganate, untrustworthy results are obtained in the case of highly saline waters, such as sea-water, even when alkaline permanganate solution is employed (see ANALYST, 1902, 341), owing to the liberation of chlorine when the solution is acidified at the end of the operation. The author describes a device for preventing this loss, consisting in a hollow stopper ground into the neck of the flask in which the reaction is carried out ; a bent tube, provided with two bulbs, leaves the top of this stopper, and the bulbs are partially filled with a 10 per cent.solution of potassium iodide, to form a trap for any chlorine liberated when the solution in the flask is acidified. After acidification, and when the colour of the permanganate has disappeared, potas- sium iodide solution is added through the trap-tube, and, after cooling, the mixed contents of the bulbs and flask are titrated with thiosulphate solution as usual. w. P. s. Quantitative Determination of Phosphorus in Solutions. A. C. Christo- manos. (Zeds. anorg. Chenz., xc., 305.) - To determine phosphorus dissolved in ether or benzene, a portion of the liquid is weighed out into a tared flask, and an excess of a 10 per cent.solution of copper nitrate in water is added. The whole is well shaken for a few minutes, and then heated on a water-bath for fifteen or twenty minutes to drive off the ether or benzene. With continuous shaking and heating of the flask bromine is next added drop by drop until the whole of the copper has been converted to cupric bromide, phosphorous and phosphoric acids being formed at the same time. The liquid is then evaporated to a low bulk, after the addition of nitric acid, to expel the bromine and oxidize the phosphorous acid, an excess of ammonia is added, and the determination completed as usual. A. G. L.THE ANALYST. 71 A Radically New Method for the Determination of Sulphur in Iron and Steels.H. B. Pulsifer. (Iron and Steel Magazine; through Clzem. News, xc., 230.)-The method essentially consists in bringing the steel into solution by a mixture of chloric, hydrofluoric, and hydrochloric acids, the insoluble residue being fused with sodium peroxide and the solution of the melt added to the main solution, in which the sulphuric acid is then precipitated as usual. In a 250 C.C. broad Jena beaker 2.5 grammes of the sample are moistened with water and then treated with 20 C.C. chloric acid (specific gravity 1-12> and a very little hydrofluoric acid. As soon as the first very violent reaction is over, 5 C.C. hydrochloric acid are added, the beaker is covered, and the whole heated to boiling to complete solution. The insoluble residue left is next filtered off, washed two or three times with a little water, dried by suction, and placed in a 20 C.C.nickel crucible. Sodium peroxide is added to it, and, whilst the cover is held down with the tongs, the crucible is heated by a strong flame. The action is over in a few seconds, and as soon as the melt is solid it is dissolved in 50 C.C. water and a little hydrochloric acid, any unburnt carbon being filtered off. The filtrate is added to the main filtrate, which in the meantime has been boiled down, after the addition of 20 C.C. concentrated hydro- chloric acid, to a volume of less than 10 C.C. The total volume of the mixed solutions should be about 100 C.C. ; barium chloride is added, and the determination finished as usual.Values found by this method for sulphur in steels generally appear to be con- siderably higher than those given by the older methods ; for cast-irons the agreement seems to be good. The proportion of sulphur in the insoluble residue, which the author treated separately for the test analyses, is considerable, in one case being over 40 per cent. of the total sulphur. A. G. L. On the Use of Phosphorous Acid for the Determination of Selenium and Tellurium. A. Gutbier. (Zeits. anorg. Cheiiz., xli., 448.)--From the analyses quoted, it appears that phosphorous acid can be successfully used for the determina- tion of selenium and tellurium when these elements are in the tetravalent condition ; solutions of selenic and telluric acid, on the other hand, are not reduced appreciably by phosphorous acid.The method used is to add a concentrated solution of phos- phorous acid to a solution of selenium or tellurium dioxide in 20 per cent. hydrochloric acid and to boil for a short time; the precipitate is filtered on a Neubauer platinum crucible, dried at 105" C., and weighed. A. G. L. A Comparative Examination of the Gravimetric Methods for the Determination of Selenium. A Gutbier, G. Metzner, and J. Lohmann. (Zeits. aizorg. Chenz., xc., 291.)-The authors have made a comparative study of the various methods of reducing selenium from solutions of the dioxide. I n all cases they have found it necessary to boil the solution with an excess of the reducing agent, and then, after apparently the whole of the selenium had been precipitated, to add a little more of the reagent, and to boil for another ten minutes. The selenium obtained was always dried at 105" C. and weighed. I t was found that hydrazine hydrate gives very good results, but a very concentrated solution of selenium dioxide must be employed. This is less necessary in the case of hydrazine hydrochloride or72 THE ANALYST. sulphate, which also give good results; with the last reagent it is necessary to acidify the liquid with hydrochloric acid. Sulphurous acid in hydrochloric acid solution also gives very good results, but large quantities of these reagents must be used. Alkali sulphites are not to be recommended, as selenium obstinately retains salts. Hydroxylamine hydrochloride gives good results only under certain conditions, and very prolonged boiling is required to complete the reaction. Potassium iodide in hydrochloric acid necessitates the use of dilute solutions, and high results are invariably obtained owing to the retention of potassium chloride by the selenium. Finally, the use of hypophosphorous acid in alkaline solution suffers from the same defects, and, further, precipitation is never quite complete. A. G. L.

ISSN:0003-2654    

DOI:10.1039/AN9053000065

出版商:RSC    

年代:1905

数据来源: RSC

摘要:

72 THE ANALYST. APPARATUS. A Modification of the Freezing-point Method. S. W. Young and W. H. Sloan. (Jouwz. Anaer. Chem. Soc., xxvi., 913.) - Instead of following the usual custom of slightly supercooling a liquid, allowing ice to form, and taking the highest temperature reached during this stage as the melting-point, the authors prefer to stir a liquid slightly above its solidifying-point with ice, and to consider the lowest temperature reached as the melting-point, since the ice will continue to melt and cool the liquid until equilibrium between the two is established. To carry out the method, a vacuum-jacketed tube, 260 millimetres long and 45 millimetres in internal diameter, is used. On the top of this rests a brass plate, a (see figure), provided I-J with three prongs, which grip the vacuum-tube firmly.On the under-side of this plate is cemented a cork which fits the mouth of the tube, Both plate and stopper are perforated so as to carry a Beckmann thermometer. At either side of this a brass tube, Q inch in diameter, soldered on to the plate, passes through the plate and stopper (b, b). These tubes serve as guides for the upright rods of the stirrer frame (d, d). Brass strips (c, c, e, e ) serve as braces to keep the arrangement rigid. At the upper brace ( e ) connection is made with a rod connected with a wheel which moves the stirrer. At the lower end of the rods is soldered the cylindrical roll of silver- foil on which the ice is to be frozen (f). To freeze the ice on the stirrer, the latter is placed in a glass tube slightly smaller than the vacuum-tube.This tube is fitted with a stopper carrying another piece of glass tubing, slightly larger than the thermometer. Cooled boiled water is poured into the outer tube, and frozen by immersing the whole in a freezing-mixture. The stirrer with the ice is then easily removed by warming the two glass tubes slightly. After removal it is placed in a second vacuum-jacketed tube, to which it is also transferred between any two determinations. One stirrer can be used six to eight times. To make a, determination, about 125 C.C. of water; cooled to nearly 0" C., are placed in the vacuum-jacketed tube, which is then put into a vessel containing ice.THE ANALYST. 73 The thermometer and stirrer are then inserted, and the stirrer is set in motion unti a constant reading is obtained.Stirrer and thermometer are then removed, a weighed amount of substance is introduced, the stirrer and thermometer replaced, and another reading taken. The whole apparatus is then taken out of the outer vessel, the stirrer and thermometer are removed after allowing them to drip for a moment, and the vacuum-tube and solution weighed. By subtracting the weights of the empty tube and of the substance added, the weight of water present is obtained, from which the concentration is calculated. This procedure is repeated several times. The results obtained in this way for the molecular lowering are very con- cordant, slightly too low, and decreasing with increasing concentration of the solution, owing to the increasing amount of radiation to the outer vessel.The authors discuss some of the sources of error, and hope to eliminate these so as to obtain still better results. A. G. L. An Improved Form of Kipp’s Apparatus. H. J. Friswell. (Chem. News, xc., 154.)-The apparatus shown in the figure differs from the usual form of Kipp in having a neck and cock (B) on the upper bulb (I), and also in being fitted with the tube A, which reaches from about three-quarters of the height of I nearly to the bottom of the lowest bulb. This tube is fixed to the bulb 1 by means of a ground- glass joint, warmed and smeared with marine glue before use. The bulb itself is fitted into the middle bulb, as usual, by a glass joint. To charge the apparatus, zinc, etc., in fairly large pieces is placed in bulb 2 ; a strong solution of zinc sulphate, etc., according to the gas to be generated, is then poured into the lowest bulb up to within $ inch from the top; and acid is then poured into the top bulb so as to stand an inch or so above the top of tube A.As soon as the stop- cock at C is opened, the acid will flow down A into the lowest bulb, and, being lighter than the heavy salt solution therein, will rise through it to the middle bulb. When the stopcock is shut the acid is forced downwards, and causes the salt solution to overflow from A into the upper bulb, where it falls through the lighter acid. As the acid becomes exhausted, the salt solution will tend to approach the top of tube A in the upper bulb, and may be drawn off through B, fresh acid being filled in through a funnel long enough to enter A for a short distance.To recharge the material in bulb 2, enough salt solution is drawn off through B to uncover the top of A, from which the greater part of the liquid is next removed by means of a long-stemmed pipette, after which the zinc, etc., is put in as usual through C ; the neck D need never be used at all. The apparatus is said to be less wasteful and easier to recharge than the ordinary Kipp form. As its economical working depends on the difference in specific74 qj P a: THE ANALYST. 1 gravity of two liquids in contact with each other, it is evident that it must not be moved about more than is absolutely necessary ; the falling of small fragments of the solid material into the lowest bulb should also carefully be avoided. A. G. L. Improved Measuring-Tube for Dumas’ Nitrogen Process. Anton Landsiedl. (Chem. Zeit., 1904, xxviii., 643.)-Greater sim- plicity and ease of working are claimed for this form of receiver. The measuring-tube is filled with mercury through the short lateral tube in the usual way, and the soda solution run in from the cup or funnel. Any air can be expelled by closing the orifice with the thumb, and admitting a little mercury from the cup, displacing the air. An additional advantage lies in the fact that, should this be necessary, further soda, can be added during the operation without danger of loss; also that, after emptying out the mercury and soda, the tube can be washed out with distilled water before being brought into the final measuring-cylinder. The apparatus may be obtained from Dr. H. Goekel, Berlin. H. A. T. Fiq. 1 Fin. 2

ISSN:0003-2654    

DOI:10.1039/AN9053000072

出版商:RSC    

年代:1905

数据来源: RSC

摘要:

74 THE ANALYST. REVIEWS. PERCENTAGE TABLES FOR ELEMENTARY ANALYSIS. By LEO F. GUTTMANN, PH.D., A.I.C. London : Whittaker and Co. By the aid of these tables the percentages of carbon and hydrogen in the substance under examination are readily calculated from the amounts of carbon dioxide and water obtained in a combustion analysis, and hence the tedious operation of working out several sums in proportion is avoided. As the tables substitute addition and subtraction for multiplication and division, accurate results are more easily attained than by the older method. The tedious task of compiling the tables has been well done; they have been carefully checked, the proofs scrupulously revised, and they are of guaranteed accuracy. The tables cannot fail to be most useful to those engaged in organic analysis, and form a welcome addition to the list of those commendable labour-saving books which have appeared of late years.A table for the reduction of volumes of nitrogen to grammes is appended. W. J. S. INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, B.A. (Oxon.), F.I.C., and T. C. HEPWORTH. Pp. xiv and 251, with 46 Illustrations, including 4 Plates. London: Charles Griffin and Co., Ltd., 1904. Price 7s. 6d. net. To all who are interested in the history and manufacture of writing and printing inks this is a most useful and interesting volume. I t s scope differs from the work on inks issued in 1902 by S. Lehner, and includes three sections : Writing Inks ;THE ANALYST. 75 Printing Inks ; and Inks for Miscellaneous Purposes, including copying, safety, marking, and other inks for special purposes. Curiously, there is no reference in the book to typewriting inks.The history of ancient writing and inks is very good, with il!.ustrations of early Egyptian writing on papyrus. Indeed, throughout the book it is exceedingly well illustrated, showing the various tannin and other ink materials more fully, I believe, than is done in any other work of the same compass. The tests and processes given for the examination of materials imply a considerable knowledge of chemical laboratory methods, and will be most useful to those who have had the requisite training. Under Printing Inks, the most recent methods employed in their manufacture and the machinery are fully described and figured, including the process of three- colour printing by which wonderful effects are obtained. The colour diagram shown here is of great interest.The register of English patents relating to inks appears a very full and complete one, and the careful way in which inEormation has been collected from widely-scattered sources renders the book a valuable one to all who take up this subject. The book is well got up, and very few slips occur in the printing. T. F. APPLICATION OF SOME GENERAL REACTIONS TO INVESTIGATIONS IN ORGANIC CHEMISTRY. By Dr. LASSAR-COHN. Translated by Dr. J. BISHOP TINGLE. 101 pp. London : Chapman and Hell, Ltd. Price 4s. 6d. net. New York: John Wile? and Sons. The subject-matter of this little work, if divorced from deplorable blemishes of translation, is excellent. I t aims at assisting the investigator to gauge, before appli- cation, the comparative value of the numerous processes which may be used for effecting any particular change necessary to the progress of his research.This, however, is not a requirement of students until they become investigators, and the present volume would quickly demoralize an individual who has not acquired a respectable literary style. Split infinitives may leave veterans unscathed, but they are bad for beginners. When the translator writes “ tetrabromoparaxylene can only be converted into tetrabromoterephthalic acid, to a very limited extent, by any of the ordinary oxidizing agents,” and then proceeds to mention an extraordinary oxidizing agent which effects the same change, he is at least intelligible, if ungrammatical; but what is the exact significance of ‘‘ tertiary isobutylglyceryl-a- is hydroxylamine obtained from nitroisobutylglycerol ” (p.56) ? “ Hyacyl,” whatever it means, may be an accident, but “hydrhaloid” seems intentional, and the intention is too CarrolisLn for use in text-books. “ Phenylsemicarbazine ” is not English, though its meaning is clear, and the same remark applies to the employment of ‘‘ substitution ” when the idea of (‘ replacement ” is intended. “ Rescorcinol ” is probably a misprint, but brom acid ” is slang, and L 6 phenyl glycocoll ” in the line next to “ phenylamin- oxalic acid” is carelessness. The work of Aschan is familiar to most readers of chemical literature, but who is ‘‘ Ashan,” a gentleman mentioned twice in the text and also in the index ? In these days of universal charity the translator’s hope that, in course of time, the blind, trial and failure process may be increasingly restricted ” (p. 2) will be condemned as heartless, and must not be taken too seriously. I n every five pages something of this order will be found to exasperate the reader, and distract76 THE ANALYST. his mind from the really valuable subject-matter; but enough has been said to indicate that no conscientious teacher should place the book in the hands of a student without grave warnings against its lamentable want of style. M. 0. F.

ISSN:0003-2654    

DOI:10.1039/AN9053000074

出版商:RSC    

年代:1905

数据来源: RSC

摘要:

76 THE ANALYST. INSTITUTE OF CHEMISTRY OF GREAT BRITAIN AND IRELAND. PASS LIST OF THE JANUARY EXAMINATIONS. OF eighteen candidates who entered for the Intermediate Examination, the following thirteen passed: S. J. M. Auld, Ph.D. (Wurzburg), S. L. Archbutt, A. W. Bain, B.A., B.Sc. (London), J. T. Cart, B.Sc. (London), T. F. Cowie, D. Gair, B. Sc. (London), C. T. Gimingham, H. G. Harrison, B.A. (Cantab.), Elsie S. Hooper, B.Sc. (London), S. G. Liversedge, W, H. Simmons, B.Sc. (London), A. S. Stockwin, B.Sc. (London), and E. J. Wilson, B.A. (Cantab.). I n the Final Examination for the Associateship (A.I.C.) in Mineral Chemistry, of six who entered, the following five passed : H. Calam, B.Sc. (Victoria), J. D. Fraser, R. F. Korte, P1.D. (Heidelberg), W. D. Rogers, Assoc.R.C.Sc. (London), and P. E. Spielmann, Assoc.R.C. Sc. (London). Of three Candidates in Organic Chemistry, one passed: H. E. Laws, B.Sc. (London); and of nine who entered in the Branch of the Analysis of Food and Drugs, and of Water, including an Examination in Therapeutics, Pharmacology, and Microscopy, .the following six passed : G. S. A. Caines, S. W. Collins, R. M. Filmer, H. E. Gresham, B.Sc. (London), V. H. Kirkham, B.Sc. (London), and J. Miller. One Candidate passed a General Practical Examination for the Fellowship (F.I.C.) :, W. H. Merrett, A.R. S.M. The Examiners in Chemistry were Mr. W. W. Fisher, M.A. (Oxon.), F.I.C., and Dr. G. G. Henderson, M.A., F.I.C. Dr. A. P. Luff conducted the Examination in Therapeutics, Pharmacology, and Microscopy.

ISSN:0003-2654    

DOI:10.1039/AN9053000076

出版商:RSC    

年代:1905

数据来源: RSC