ISSN:0003-2654    

DOI:10.1039/AN87803FP001

出版商:RSC    

年代:1878

数据来源: RSC

ISSN:0003-2654    

DOI:10.1039/AN87803BP003

出版商:RSC    

年代:1878

数据来源: RSC

摘要:

THE ANALYST. Two years ago, when THE ANALYST first appeared, there were not a few prophets who predicted that a small society, such as the Society of Public Analysts must ever be, could not maintain a monthly journal of its own. Such views naturally received ready credence from those who, because they were not actually analysts in practice, were not eligible to be become members of the society.The appearance of our twenty-fifth number, commencing our third volume, will go far to disabuse the minds of tbose who still cherish such an opinion. The object laid down in the first number of THE ANALYST was not only to print all papers read before the Society but to supply such information on technical points, both of general analysis and food analysis, as should meet the requirements of the ordinary analyst, and to furnish reports of such typical caaes of adulteration proceedings, and other law cases in which chemical points were involved, as should furnish a permanent record for reference.When at the end of the first year a difficulty arose in consequence of a society which isnot chartered, being the owner of a copyright, a slight alteration was made to meet this difficulty, and the journal having passed into the hands of its present proprietors, a new feature was added in the form of editorial articles and notcs on the questions which fiom time to time disturb even the quietude of laboratories. How far we have succeeded in our task must be for our readers to judge. We can only form our opinion from our increased and increasing circnlation, and from the fact that nearly every technical journal quotes from our pages. One feature of the present number, which will doubtless be examined with interest, is our annual return of the work done under the Sale of Food and Drugs’ Act.We have not space to refer to this fully this month, but in our next number we shall make a comparative analysis of the results of the last and previous years.The past year has been marked in the chemical world by the formation of the Institute of Chemistry. This company has not been formed on the same basia as the Society of Public Analysts. To become a member of the latter society it is neeessary that the applicant should be an analyst in practice, even assistants not being eligible, whereas to become a member of the Institute it has hitherto been simply nacesaary that the council should ‘‘ admit ” the would-be member, as the qualification clauses are only to be enforced in the future. The Council have exercised this right to admit freely, and our readers will judge how far the criticisms we have considered it our duty to publish on the scheme were well founded, when we point out that nearly one half of those whom they have admitted have not accepted the proffered honour and ‘‘ liability.” Evidently, therefore, the mode of organization adopted did not commend itself to many of the elected five hundred, any more than to our correspondents and ourselves.Opinions are expressed in certain legal circles that the company doe8 not really fall within t.he scope of the Companies’ Act; if this is the case what is the penalty, surely there must be Borne 3 Unlimited 2ia6iZity.” which is not a rery pleasant outloQk for the aharebolders, espeoially if eveip member is a Ehareholder.One word more, The answer a correspondent gives is,THE ANALYST. ~ ~ ~~~~ ~ A very unseemly difference has occurred during the year between the Public Analysts and the chemists in the Inland Revenue Laboratory. Differences of samples may of course be expected to occur occasionally, and then, if a sample has been changed either wilfuIly or by accident, an analyst must be expected to find different results.The matter becomes much more sericus when the results obtained are identical, but the deductions drawn from these results are different, when, in fact, chemista put on one side the accumulated experience of years, and work on new data. Still more is there ground for regret when the application of our Society for the publication of those data in the only effectual way ie refused. As to the original papas which have been published in the last year, our index must speak. We shall endeavour to keep up to and even excel our present etandard in the coming year, and to this end shall gladly receive any contribution containing the results of original research on any chemical subject.

ISSN:0003-2654    

DOI:10.1039/AN8780300229

出版商:RSC    

年代:1878

数据来源: RSC

摘要:

THE ANALYST. ON THE FATTY METAMORPHOSIS OF THE ALBUMINOIDS IN MILK AND CHEESE. By A. WYNTEB BLYTH, M.R.C.S. Bead before t h Asociety of Public dna&ts, on 20th Fekuary, 1078. h 1864, 1\6. Ch. Blondeau contributed to the Annalos de Ch6mie et de Physique (4eme 8erie. t. 1) his research on the changes which the ltoquefort cheese underwent probably from the influence of mycoderms. A portion of a typioal cheese was taken and divided into four parts; the h t Wm analysed at once, the three others were replaced in cellars and analyeed after one month, two months, and a year’s respective sojourn.THE ANALYST.2 3 1 (1.) The fresh cheese had the following composition :- Caseine . . . . . . . . . . . . . . . . . . . . . 81.03 Chloride of sodium . . . . . . . . . . .. . . . . . . 4-40 F a t . . . . . . . . . . . . . . . . . . . . . . . . 1.85 Lactic acid . . . . . . . . . . . . . . . . . . . . . 0.88 Water . . . . . . . . . . . . . . . . . . . . . 11.84 (2.) The piece which had remained in the cellars a month had all the appearance The of a fatty body; its odour had changed, and its taste was sweet and agreeable. analysis shows that a largs portion of the caseine had undergone fatty change.Caseine . . . . . . . . . . . . . . . . . . . . . 61 *33 Fat . . . . . . . . . . . . . . . . . . . . . . . . 16’12 Chloride of sodium . . . . . . . . . . . . . . . . . . 440 Water . . . . . . . . . . . . . . . . . . . . . 18 *16 (3.) The piece which had remained in the cellar two months was exactly in the There was a still further development of fat, and the fat itself condition most prized.had become partially decomposed into fatty acid. Caseine . . . . . . . . . . . . . . . . . . . . . 43.28 Margarine . . . . . . . . . . . . . . . 18-30 *at { Oleine . . . . . . . . . . . . . . . 14.00 ] 32*30 Butyric acid . . . . . . . . . . . . . . . . . . . . . 0.67 Chloride of sodium . . . . . . . . . . . . . . . . .. 4.45 Water . . . . . . . . . . . . . . . . . . . . . 19-30 (4.) The fourth portion, kept a year, had acquired a strong odour and a pungent Ammoniacal salts of the fatty acids were formed, and there was a still further taste. diminution of the caaeine and an increase of fatty products. Caseine . . . . . . Margarine . . . . . . Oleine.. . . . . . . . Butyrate of ammonia Caproate of ammonia Caprylate of ,, ...Caprate of ,, ... Chloride of sodium ... Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40.28 16.85 1-48 5-62 7.31 4.18 4.21 4 *46 16.62 This research appears to have attracted but little notice, yet, despite of its incom- pleteness, I cannot but consider it as a path-breaking one, and likely t o be of considerable and practical interest to those engaged in the examination of foods.I have analysed a large number of cheeses, in order to follow up a similar line of investigation, the time has, however, not yet elapsed for their re-analysis, and I there- fore shall confine my remarks to the analagous change taking place in milk.That there is really an increase of fat in decomposed milk, I believe can be established not alone from experiments or analyses undertaken with the special object in view of investigating the question, but also from what may be called accidental experiments.(1,) A sample of rcfore” milk, which in its time WGS rather notorious, was analysed by the writer on July 17th :- Solids not fat . . . . . . . . . . . . . . . . . . . . 9.70 Fat . . . . . . . . . . . . . . . . . . . . . . . . -20 Ash . . . . . . . . . . . . . . . . . . . . . . . . -7 1232 THE ANALYST. Circumstances arose rendering an analysis by another chemist desirable.It Was submitted t o Mr. Wigner, who found about three weeks afterwards- Solids not fat . . . . . . . . . . . . . . . . . . . . . 8.96 Fat . . . . . . . . . . . . . . . . . . . . . . . . -76 Ash . . . . . . . . . . . . . . . . . . . . . . . . ‘74 Free acidity calculated as Laetic Acid, 73 per cent. (2.) Almost every sample of milk which has heen analysed by a second chcmisk on record in the pages of the Anazylst, shows an increase of fat. Thus a milk analysed by Dr.C. Brown * on the 28th of April, gave but 2.68 per cent. of fat, the same milk on May 9th, 2.98 per cent. of fat; and the same milk, analysed by Mr. Wm. Thompson, on May I5th, ga7e 3.017 per cent. A milk analysed by Ur, Hill,+ gave, on the 1st of March, 2.47 of fat, the same sample was returned by the Inland Revenue chemists, on the 20th of March, as con- taining 2-83 per cent.of fat. (3.) The writer analysed, very carefully, two samples of milk from Stonehouse, on the 20th December, 1877. Each milk was analysed twice, and there was a close agreement between the analyses. Dec. 20, 1877. (1.) Caseine and milk sugar . . . . . . . . . . . . . . . 8-19 Fat . . . .. . . . . . . . . . . . . . . . . . . 2-09 Ash . . . . . . . . . . . . . . . . . . . . . . . . -62 Solids not fat . . . . . . . . . . . . . . . . . . . . . 8.81 Fat . . . . . . . . . . . . . . . . . . . . . . . . 1.33 Ash . . . . . . . . . . . . . . . . . . . . . . . . -65 Solids not fat,.. . . . . . . . . . . . . . . . . . . 9-11 (2.) Caseine and milk sugar . . . . . . . . . . .. . . . 8.46 The one was certified deficient in cream, and adulterated with water, the second deficient in cream only, and both were submitted to Somerset House ; No. 1 alone reaching their laboratory; No. 2 bursting the bottle. The Inland Revenue chemists found, (analysed probably between 4th and 8th of January, 1878), (1) Solids, not fat . . . . . . . . . . . . . . . . . . . .. 7.84 Fat . . . . . . . . . . . . . . . . . . . . . . . 3.38 Ash . . . . . . . . . . . . . . . . . . . . . . . . 068 And they certified that there had been no abstraction of cream, but a small addition of water. On examining the second sample, that is the one which through mis-fortune did not reach Somerset House, and which on the 20th of December, gave only 1-33 per cent. of fat.I found on the 23rd of January its composition, as follows :- (2) Solids, not fat . . . . . . . . . . . . . . . . . . . . . 7.62 Fat . . . . . . . . . . . . . . . . . . . . . . . 1.79 Ash . . . . . . . . . . . . . . . . . . . . . . . . -66 Acidity calculated as lactic acid -507 per cent.+ Further, the No. 1 milk which yielded t o me on the 20th Deccmber, 2.09 per cent, of fat, and to the Government chemists on the first week of January, 3.30 per cent.of fat, on examining it on the 23rd of January, I found 3.919, or nearly 4 per cent. of fat, therefore there can be no reasonable doubt that in this particular sample of milk in about a month the fat nearly doubled in amount. * Analyst, R’o. 18, Sep., 1877. t It is almost unnecessary to state that the lactic acid was neutralized before extracting with ether.THE ANALYST.233 I now come to few analyses made specially to trace the changes in decompoeed milk. (1.) A milk analysed on the 24th January :- Sp. 0. . . . . . . . . . . . . . . . . . . . . . 1032.1 Fat . . . . . . . . . . . . . . . . . . . . . . . . 3-52 Milk sugar . . . . . . . . . . . . . . . . . . . . . 4.88 Albuminoids .. . . . . . . . . . . . . . . . . . . . 4.25 Ash . . . . . . . . . . . . . . . . . . . . . . . . -72 The same sample was divided into two parts-the one was put in a perfectly clean bottle, the other was contaminated with a droplet of the No. 1 Stonehouse milk before spoken of. The uncontaminated milk 21 days after ga-ie 3-41 per cent. of fat, 3.00 of milk sugar, -009 per cent.of acetic acid, ,126 per cent. of lactic acid, and -0267 per cent. of alcohol, so that there was certainly no increase of fat, but some slight lactic fermentation, as eridenccd by lactic acid, alcohol and oxidised alcohol. The same milk which had been seeded with the ferment analysed at the same time, via, 21 days afterwards, gave 3.9 per cent. of fat. Acetic acid, alcohol, lactic acid, and milk sugar mere not estimated through accident. (2.) A milk analysed January 27th gaye the following results : - Fat .. . . . . . . . . . . . . . . . . . . . . 2.584 per cent. Milk sugar . . . . . . . . . . . . . . . . . . 4.566 Albuminoids . . . . . . . . . . . . . . . . . . . . . 5.492 Ash . . . . . . . . . . . . . . . . . . . . . . . -720 ... The same milk 18 days afterwards gave Fat .. . . . . . . . . . . . . . . . . . . . . . 4- 09 Mi€k sugar . . . . . . . . . . . . . . . . . . . . . 2. 76 Lactic acid . . . . . . . . . . . . . . . . . . . . . -1 19 Acetic acid . . . . . . . . . . . . . . . . . . . . . -002 Alcohol. . . . . . . . . . . . . . . . . . . . . . -0145 Albuminoids (by difference) . . . . . . . . . . . . . . . 3.100 Ash . . . .. . . . . . . . . . . . . . . . . . . . .72 This milk had a creamy appearance, there is a marked increase in the fat. (3.) A milk analyscd by Mr. Wigner on the 3rd of Sept., 1878. Total solids . . . . . . . . . . . . . . . . . . . . . 11-66 Fat . . . . . . . . . . . . . . . . . . . . . . . . 1-14 Solids not fat . . . . . . . . . . . . . . . . . . 9-82 The same milk analysed by the writer about 5 months afterwards on Feb.3 4 1878. Total solids . . . . . . . . . Fat . . . . . . . . . . . . Milk sugar . . . . . . . . . Alcohol . . . . . . . . . Acetic acid . . . . . . . . . Lactic acid . . . . . . . . . Ammonia in combination ... Total nitrogen by combustion A8h . . . . . . . . . . . . . . . . . . . . . . . . 8. 37 . . . . . . . . . . . . 1. 19 . . . . . . . .. . . . 2. 30 . . . . . . . . . . . . .009 . . . . . . . . . . . . ,013 . . . . . . . . . . . . -361 . . . . . . . . . . . . *070 . . . . . . . . . . . . * 69 . . . . . . . . . . . . 71 I n this caw the fat was not increased but diminished. The whole of the volatile acids present are returned as aretic, a small portion of which was, however, bntyric, or some other volatile fatty acid.The milk had an acetic ether odour.234 THE ANALYST. (4.) Another milk analysed by Nr. Wigner on the 7th of Sept., 1877. Total solids . . . . . . . . . . . . . . . . . . . . 10.615 Solida not fat . . . . . . . . . . . . . . . . . . . . . 8.016 F a t . . . . . . . . . . . . . . . . . . . . . . . . 2,600 Ash . . . . . . . . . . . . . . . . . . . . . . . . *635 Chlorine .. . . . . . . . . . . . . . . . . . . *061 The same milk analy'sed by the writer 5 months afterwards. Total solids . . . . . . . . . . . . . . . . . . . . 9. 40 Fat . . . . . . . . . . . . . . . . . . . . . . . . 3. 89 Albuminoids . . . . . . . . . . . . . . . . . . . . . 2. 00 Milk sugar . . . . . . . . . . . . . . . . . . . . . 2. 31 Alcohol . . . . . . . . . . . . . . . . . . .. . *213 Lactic acid . . . . . . . . . . . . . . . . . . . . . ,548 Acetic acid . . . . . . . . . . . . . . . . . . . . . -386 Ammonia in combination . . . . . . . . . . . . . . . ,020 Total nitrogen by combustion . . . . . . . . . . . . -313 Here, again, although the milk is the same age as the former sample, there is a very The milk had an odour of acetic ether-there were small marked increase of fat.quantities of one or more yolatile fatty acids present. (5.) A milk analped by Mr. Wigner in November :- Total solids . . . . . . . . . . . . . . . . . . . . . 10.77 Solids not fat . . . . . . . . . . . . . . . . . . . 8. 6 Fat . . . . . . . . . . . . . . . . . . . . . . . . 2-62 The Eame milk analysed by the writer 24 months after date :- Total solids . .. . . . . . . . . . . . . . . . . . . 7.52 F a t ... . . . . . . . . . . . . . . . . . . . . . 2.98 Solids not fat . . . . . . . . . . . . . . . . . . 4.56 Milk sugar . . . . . . . . . . . . . . . . . . . . . 2.10 Albumin oids . . . . . . . . . . . . . . . . . . . . . 2.1 0 Lactic acid . . . . . . . . . . . . . . . . . . . . . *081 Ammonia in combination . . . . . . . . . . . . .. . -012 Total nitrogen by combustion . . . . . . . . . . . . *337 Alcohol not estimated. I n this case there was a considerable development of acetic acid, the odour of acetic ether was very powerful, and the fat is slightly increased. The method of analysis it is, perhaps, right to mention. The fat was weighed directly, and dissolved out by ether from the solids, first made perfectly neutral by sodic carbonate, the milk sugar was converted into grape, and determined by copper solution, the precipitated sub-oxide being dissolved in acid, and deposited as copper by electrolysis on platinum foil, and then weighed.The alcohol was obtained by re-distilling the distillate, and subsequently oxi- dising into acetic acid, as in the method recommended by Dr. Dupr6.The volatile acid returned as acetic was principally, but not entirely, that acid. The alcohol calculated as ethylic was also probably a mixture of other alcohols. Tho other determinations require neither comment nor explanation. As we all know what is usually called the caseine of milk is really four albuminoid bodies, viz., true caseine, albumin, lactoprotein, and nuclein. The last was, I think, discovered in milk by Lubavin, and is in very small quantity.What share the albumin and the caseine take in the production of fat remains an, interesting subject for investigation, and also what other bodies are formed. I n the course of these few experiments I have found thatTHE ANALYST, 235 in decomposed milks nearly the whole of the nitrogen they contain may be obtained by first distillation with sodic carbonate and then with alkaline permanganate, and not as would be the case were the structure of the caseine and albumin unaltered a fractional part only. I would also point out that the fatty degeneration of muscular fibre one so often observes in dissecting rooms, the formation of adipocere, and the drops of oil appearing with more or Iess rapidity in the nuclei or bioplasm of animal cells, are examples of the fatty trans- formation of albuminous and fibrinous substances, which, so far as we know, are constructed on the same type as the milk alhuminoids. The bearing of this subject in the reference of samples to Somerset House is obvious, I believe by a very thorough examination of a decomposed milk, it will be possible even after five or six months to build up by calculation its original parts, but tho subject requires much work, and I will therefore not commit myself to any definite opinion, but trust to make one or two communications on this subject at some future meeting of the Society.

ISSN:0003-2654    

DOI:10.1039/AN878030230b

出版商:RSC    

年代:1878

数据来源: RSC

摘要:

THE ANALYST, 235 NOTE ON AN INGENIOUS ADULTERATION OF MILK, BY DR. J. MUTER. Read befors the Society of Public Analysts, on the 20th February, 18%. Fat . . . . . . . . . . . . . . . 2.1 Solids not fat . . . . . . . . . . . . 8.3 Total . . . . . . . . . . . . 10.4 Ash . . . . . . . . . . . . . . . .6 I was, however, struck by the very low ash, a somewhat unusually hygroscopic appearance about the residue, and a taste which indicated a much higher degree of SOHE time ago I received a sample of milk which, on analysis, gave :- dilution than full analysis, that indicated by the above figures, which gave :- I accordingly set to work to make a Fat .. . . . . . . . . . . . . . 2.10 Sugar (taken by Fehling) . . . . . . 2.70 Casein . . . . . . . . . . . . . . . 3.35 Ash .. . . . . . . . . . . . . . .50 Total . . . . . . . . . . . . 8.65 Here, therefore, were only 6.55 true solids (not fat), showing, as I expected, a much larger quontity of water. After numeroug researches, I at last found that the foreign matter in the milk was glycerine, which is certainly a most ingenious addition, as a solution of that body in water of 12 per cent. strength has a specific gravity of 1.030 ; and I found, after several experiments, that 35 per cent. of such glycerine water might be added to milk without being detectable either by gravity or by the ordinary ‘‘ solids not fat” process.Moreover, such an amount does not give any extraordinary sweetness easily detectable by the taste. The following is the modification of Mr. Wanklyn’s process, which I have devised to meet this case :- - (I.) Evaporate, aa uaual, and weigh the residue, (2.) Extract the residue with pwe anhydrous ether, and weigh the fat or the solidr not fat whichever the operator may prefer,236 TIIF, ANALYST.(3.) Extract the solids not fat with a mixture of eb8oZzlte alcohol and ether, in equal volumes, and evaporate the solution at a gentle heat.Any oily-looking liquid that ie left should now be tested for glycerine, by warming with a little sulphuric acid, and getting off the fumes of acrolein. If this be found the solids not fat are perfectly unreliable, and nothing remains but to make a full analysis of the milk, estimating both the sugar and the casein directly-the former by Fehling’s solution and the latter by precipitation.If the Fehling be used gravimetrically it should be borne in mind that the true equivalent,.as shown in my manual of chemistry, is not that usually given, but is 100 parts milk-sugar = 147.76 parts CUO. (4.) The ash must be taken on a separate portioa In case the milk be sour it must be carefully neutralised by a known weight of sodium-carbonate before evaporating. This difference between the true and the apparent solids not fat will indicate the amount of (( glycerine-water” added, and if the gravity of the milk is about 1.030 it is then safe to call 12 per cent. of that glycerine and the rest water. Of course as the glycerine is slightly volataised during the evaporation, the estimation will always be something under the truth.

ISSN:0003-2654    

DOI:10.1039/AN8780300235

出版商:RSC    

年代:1878

数据来源: RSC

摘要:

236 TIIF ANALYST. EXPERIMENTS ON THE CHEMICAL ACTION OF CHLORATE OF POTASH ON THE SYSTEM. By OTTO HEHNER F.C.S. Read before the Society of Public Analysts oa 20th February 1878. CHLORATE of Potash mas formerly frequently administered as a medicine with a view of supplying oxygen to the system in cases of defective oxydation. It was thought doubtless, tbat since oxygen is readily obtained from it by the action of heat it must undergo similar decomposition in the animal body. But after some investigations of Wiihler and Ptehberger who recognized chlorate of potash in the urine of patients who bad taken it this opinion was abandoned as altogether erroneous and in all books on Pharmaceutical Chemistry and Materia &fedica the statement is now to be found that chlorate of potash passes through the system without any decomposition.But this Statement true though it may be seems at least to be baaed on very slender evidence ; the mere " recognizing ' j in the urine of the salt cannot be considered conclusive as to the inertness of the compound. And since chlorate of potash besides being a powerful diuretic undoubtedly possesses other valuable medicinal properties I have at the request of Dr. Sinclair Coghill of Ventnor undertaken a series of experiments with a view to arrive a t a definite conclusion. Whilst I have thus worked tit the chemical side of the question Dr. Coghill has inrestigated the medi'cal part and his results will be published in a medical paper. Since the works on Analytical Chemistry did not supply me with any information as to any method for the quantitative determination of chlorate of potash in a liquid like urine in the presence of much chloride and organic matter I will embody iu this paper the description of the several methods which I have used.I n the three series of experiments which I am about to describe three different methods of analysis were employed. I n the first the chlorine present as chloride was determined by means of a standard silver solution (1 c.c = 0.00355 grm. C1) after the organic matter had as fa THE ANALYST. 237 possible been destroyed by means of a solution of permanganate of potash the dioxyde of manganese which had copiously come down having been removed by filtration and thoroughly washed with boiling water. I n another quantity of the urine the total chlorine waa determined volumetrically after incinerating the urine with the addition of a little nitrate of potash dissolving the white mass in water acidulating slightly with nitric acid and neutralizing the acid by the addition of pure carbonate of lime.The difference between the two determinations was calculated for K C1 03. Although on testing this method by analyzing a urine t o which a known quantity of K C10 had been added I obtained very fair results yet I abandoned it in the second series for two reasons. First because on incineration a little chloride may be volatilized ; and second because some chlorate may escape perfect decomposition. In the second series of experiments I employed as a reducing agent the copper-zinc couple described by Messrs.Gladstone and Tribe. This ueeful couple is prepared by pouring over 1 metre of well-crumpled Fery thin zinc foil cut in shreds a solution of 15 grms. of sulphate of copper the resulting black spongy mass being well washed with water. It decomposes water even at ordinary temperature with the evolution of hydrogen, whilst near tho boiling point the reaction is exceedingly active. It readily reduces chlorate of potash in Eolution as has been shown by Thorpe and by Gladstone and Tribe, and is more clearly seen from the following experiments :-Twenty-five C.C. of a solution containing 0.25 grm. K C1 0 were boiled for five minutes with a quantity of the couple the liquid was filtered the precipitate washed with boiling water and the chlorine titrated by means of standard silver solution Used 5.10 C.C.equal to 0.0625 grm. K C1 0 or 25.00 per cent. After ten minutes’ boiling 9.0 C.C. silver solution were used equal to 0.1103 grm, K C1 Os or 44.12 per cent. After twenty minutes 14.9 C.C. = 0.1827 grms. K C1 0 or 73.08 per cent, After half-an-hour’s boiling 20.34 C.C. of silver solution were used correBponding to 0.2494 grms. K C1 0 or 99.76 per cent. of the total amount taken. Hence at boiling temperatures the reduction of chlorate in aqueous solutions by means of the couple is very rapid. At ordinary temperatures however the reduction is slow. Thus allowing 25 C.C. of chlorate solution to stand over night with a considembh quantity of the couple only 4.4 C.C. of standard silver solution were used, equal to 0.0539 grms.K C1 0 3 or no more than 21.56 per cent. of‘ the chlorate had been converted into chloride. 25 C.C. of urine and 25 C.C. of the above chlorate solution were boiled for one hour with the couple the total chlorine was then determined and from it t.he amount of chloride contained in the urine wa8 subtracted. Only about 50 per cent. of the chlorate taken were founa to have been reduced. After 3 or 4 hours’ boiling however the total amount of chlorate had been converted into chloride the determinations coming t o within 1 milligram of the quantity taken. In these experiments the couple was added gradually so as always to ham an active evolution of hydrogen from the liquid. Although however the reduction of the chlorate was quite perfect the method was found to be troublesome on account of the persistent frothing of the urine and its The reduction is also far slower in urine than in pure water 238 THE ANALYST.liability to run over. Moreover in the dilute liquids with which I had to deal the difference between the determinations of the chloride and of the total chlorine was often very small and the slightest mistake was enormously multiplied in calculating from the small volume analysed to the total volume of urine voided I therefore in the last series of experiments made employed a tbird a gravimetrical and eminently satisfactory and simple method. I removed from a measured quantity of the urine the chlorine present as chloride by means of an excess silver nitrate rendered the filtrate acid with dilute sulphuric acid and added metallic zinc.Chloride of silver was at once formed, but by the further action of the zinc this was reduced leaving the fluid quite clear, into metallic silver which was washed first with water then with dilute ammonia, and in the filtrate the hydrochloric acid was precipitated with silver nitrate the precipitate being collected and weighed. The reduction is finished in about half-an-hour if the liquid be very gently warmed. The reduction was also tried after the removal of the chloride as above by means of an acid solution of ferrous sulphate. On heating the chlorate is readily converted into chloride and separates as chloride of silver. I found this method to be the best, simplest and quickest qualitative test for chlorate being far Euperior to the usual incineration method where loss by volatilisation is very possible.The test in fact, is quite as sensitive as that for chloride and quite as simple. As I do not find it described in any test book I hare consulted I recommend it here most emphatically, and consider it the more useful in qualitative analysis since at the same time the nitrates are indicated before heating the liquid. I further investigated the Indigo method but found that however exact it is in aqueous solution it is not applicable to liquids containing large quantities of organic matter such as urine. I now proceed to the experiments themselves. I. SERrEs. An inmate of the Ventnor hospital took on six successive days in four portions daily doses of 120 grains (or 7.776 grms.) or 720 grains in all of chlorate of potash.The urine was collected the daily quantity measured and sampled The following results are caloulated for each day’s volume :-1st day.-Excreted 7.27 grm. total chlorine and 6.20 grm. as chloride; difference, 2nd 3rd 4th 5th 6th 7 th 1.07 grm. C1 as chlorate equal to 3.69 grm. K C1 0 or 47.5 per cent. of the daily dose. day.-7.64 total C1 5.34 as chloride = 2.30 C1 as chlorate equal to 7.94 grm. K C1 0; or 102.1 per cent. of a dose. day.-7.418 total Cl 4.772 as chloride = 2.646 C1 as chlorate or 9.138 grm. I( C1 O3 or 117.5 per cent. day.-6.26 grm. total C1 4.25 as chloride or 1.91 ns chlorate equal to 6.59 grm. IC C1 O3 or 84.8 per cent. day.-Total C1 8.84 grm, 5.79 as chloride; difference 3.05 as chlorate or 10.33 grm.K C1 0 = 135.4 per cent. day.-Total C1 3.27 as chloride 3.05; difference 0.22 C1 ’= 0.76 grm. K C10 = 9.7 per cent. day.-Total C1 4.45 grm. as chloride 4.47 grm. therefore chlorate absent. Obtained therefore altogether 497.0 per cent. of the daily dose or 82.8 per cent of the total chlorate taken THE ANALYST. 239 On account of the great irregularities in the amounts of chlorate in the urine and also on account of the fact that though six doses were meaeured out to the patient yet chlorate was only founci on six instead of on seven or eight days I thought I had good reason to place but little reliance on the above series and I felt certain that if accurate results were to be obtained I must make myself the vehicle of the chlorate. I determined at the same time to ascertain the rate at which the excretion of the chlorate takes place.XI. SESIES. I took exactly 2 grms. of pure and dry chlorate and separately collected and analysed every batch of urine passed. Every analysis was made twice, the average being taken for calculation. Already 1 hour 30 minutes after the taking of the dose I found 0.3446 grm. K C1 0 or 17.23 per cent. of the dose in the urine. After another 2 hours 0.4724 grms. or another 23.62 per cent. were found. I n the third batch passed 2 hours later 0.3217 K C1 0 3 or 16.08 per cent. of a dose were contained. In the fourth passed after another 2 hours 55 minutes I found 0.2182 grm. K C1 Os or 10.91 per cent. Next morning 20 hours 25 minutes after the commencement of the experiment 0.3002 grm. K C1 0 mere found or 15.01 of a dose In the sixth sample in which owing to an accident I unfortunately could only make one and that one a very doubtful analysis passed 9 hours 15 minxtes after the last sample 0.2196 grm.K C1 0 were contained equal to 10.98 per cent. The seventh sample was free from chlorate. Altogether therefore of 2 grms. of chlorate taken 1.8764 grm. or 93.82 per cent. had passed through the kidneys. The rate of excretion calculated per hour was therefore as follows :-1st experiment.-Per hour for 14 hours . . . . . 2nd 92 , , 2 , . . . . . . 11.81 ,, 4th 9 , , 2 , 55 minutes 3.74 ,, 6th 9 9 j 9 9 12 $ 9 . 1.25 ,, 6th ). , , 9 , 15 minutes 1.18 ,, 11.49 per cent. 3rd YV , , 2 , . . . . . . 8.04 9, The latter figure is I believe a little too high.2 grms. though a somewhat large dose ia rather a small quantity considering that it has to be determined in a very large bulk of fluid. The results must therefore necessarily be a little doubtful. Yet it is satisfactory to get out of the whole body 1.8764 grms. with the loss of no more than 0.12 grm. I therefore took within 2 hours or so 8 grms. of pure chlorate of potash and carefully collected all urine passed for nearly 3 days namely until a qualitative test for chlorate gave a negative result. The amount collected was nearly 4 litres. I mixed the different portions and made up with distilled water to 4000 C.C. From 40 C.C. the chlorides were removed as described in an earlier part of this paper, and the chlorate reduced with zinc and sulphuric acid; 0.0884 grms.AgCl were obtained. A second experiment also yielded 0.0884 AgC1 corresponding to 0.07552 grm. K C1 0, or 7.552 in the total volume. 94.40 per cent. of the chlorate taken have therefore been excreted by the kidneys in an unaltered state. Whether the remaining six per cent. were decomposed in the body-were evacuated with the feces or were only very gradually and imperceptibly eliminated I am unable to decide. My impression is that they were not decmposed because if such reduction 111. SERIES 240 THE ANALYST. took place it ought to have been proportionately much greater in the case of the small dose than in the large dose taken. The saliva turns intensely acid whilst chlorate remains in the system. The acidity is however not due to free hydrochloric acid. Urine containing chlorate remains free from smell for a considerable period, although bacteria develop very plentifully in it. This fact bears out a statement of Royle and Headland in their Materia Medica p. 96 namely that chlorate was 4' supposed to counteract putrescence of the fluids in scarlatina typhus cholera &c.)

ISSN:0003-2654    

DOI:10.1039/AN8780300236

出版商:RSC    

年代:1878

数据来源: RSC

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240 THE ANALYST. ON THE DETERMINATION OF SULPHURIC ACID IN URINE. BY E. BAUMANN. Translated from th Zeitschrijt far Physiologische Chemie, aol. 1, page 7. I HAVE already called attention t o the occurrence and origin of numerou8 componnds found in the animal body, which have the common property of being split up into sulphuric acid and aromatic compounds on treatment with mineral acids. They originate in the animal body from preformed sulphuric acid, so that they must not be looked upon as a separation of the sulphur but of the sulphuric acid. The method which has been usually adopted for the determination of the ever- present (in normal urine) sulphuric ethers, vie., precipitation of the hydrochloric acidified urine with barium chloride, does not give correct information respecting the amount of sulphates present, and it is necessary to apply a correction t o the statements hitherto made a3 to the amount of sulphuric acid in urine.Having produced several of the above-named substances in a pure condition, and after their properties and chemical constitution are well known, I do not consider it superfluous to fix upon a simple method of determining the sdphuric acid and the copulated sulphuric acid in urine.None of the copulated sulphates hitherto found in urine are decomposed by gently heating with dilute acetic acid for one hour; but they are entirely split up when warmed for a few minutes with the smallest quantity of hydrochloric acid, or if left for some hours without warming ; therefore the salts present, as sulphates in urine, can only be determined by acidifying with acetic acid.25 or 50 C.C. urine are treated with acetic acid, an equal volume of water is added, together with an excess of barium chloride. The whole is heated in a water bath until precipitation is complete and the supernatant liquid clear. This takes about half to three-quarters of an hour. The filtered precipitate gives the amount of sulphuric acid present as salts.The filtrate is treated with dilute hydrochloric acid and warmed until the precipitate, which is formed, has completely separated. (I have formerly left it to stand for one hour in a warm place, in order to ensure decomposition of the copulated sulphates.) This second precipitate contains, along with barium sulphate, a brown resinous substance, of which the greater portion can be removed by washing with hot alcohol. From the weight of this second precipitate the amount of copulated sulphurio acid can be calculated ,

ISSN:0003-2654    

DOI:10.1039/AN8780300240

出版商:RSC    

年代:1878

数据来源: RSC

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THE ANALYST. 241 BUTTER AISAXYSIS. BY F. P. PERKINS, Public Analyst for Exeter. I HAVE lately been making experiments with butter fat, and I find that the volatile acids may be estimated very fairly in the following way. I give the (( modus operaudi " in full, From 3 to 4 grammes of the purified fat are taken, saponified in the usual way and allowed to cool, dilute sulphuric acid is then added until tho insoluble acids rise to the surface, the flask is allowed to stand for a time and the liquid when clear is passed through a weighed filter paper, warm water is poured into the flask, a rotatory motion is given, and the layer of acids, broken up into a thousand globules, well washed.Allowed again to cool the wash water is passed through the filter, this operation is repeated many times, using altogether about 300 or 400 C.C.of water. The insoluble acids are then brought on the filter, washed with warm water, dried at 110 C. and weighed. I n 200 C.C. the acidity is determined with decinormal K Ho, another 100 C.C. are boiled until reduced in bulk to 10 c.c., water is added and the acidity again taken. By mbtracting the figures of the second experiment from those of the first, and multiplying by 5, an estimate is obtained, expressed in cubic centimetres of K Ho of the acidity due to volatile acids.All that is now required is t o translate this into Butyric acid and to calculate the percentage from the amount of butter used. The following table shews the degree of accuracy with which the process can be worked : 4.387 grammes of butter fat taken.Acidity due to volatile acids= 34.7 C.C. of decinormal sol. of soda = 6.9 p.c. butyric acid. 2-47 grammes of the same butter fat taken, 86-72 p.c. of insohble acids obtained. Solution of volatile acids made up to 500 C.C. Acidity due to volatile acids = 19-6 C'C. of decinormal solution of soda = 6.9 p.c. butyric acid. Exp. 3. 3.004 grammes of butter fat taken, giving 86.58 p.c. of insol.acids. Solution of volatile acids made up to 530 C.C. Acidity due to volatile acids = 21'9 C.C. of decinormal sol. of potash = 6 4 p.c. butyric acid. Exp. 4. Another portion of the same sol. Acidity due to volatile acids = 20.8 decinormal sol. of potash = 6.1 p.c. butyric acid. Exp. 6. 2.3 grammes of beef fat taken. Filtrate from insol, acids made up to 600 C.C. Acidity due to volatile acids = 4.4 C.C. decinormal sol. of potash = 1.6 butyric acid. The filtrate containing the volatile acids is made up t o 5.00 C.C. Exp. 1. Exp. 2. Solution of volatile acids made up to 600 C.C. The butter used in these experiments was pure Devonshire. It appears to me that thus simply butter may be shown to be adulterated or not, if the volatile acids do not come up to a firsed standard.

ISSN:0003-2654    

DOI:10.1039/AN878030241b

出版商:RSC    

年代:1878

数据来源: RSC

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242 THE ANALYST. REV1 E W S . The London Water Supply, by Dr. Meymott Tidy”. An Examination of the Figures and Statements published as the Results of the Analyses of Professor Frankland on the London Water Supply in 1876 and 1877, by Qt. Dr. Tidy’s volume is not merely his annual report to the Society of Medical Officers of Health, but it is a most elaborate and carefully prepared tabulated statement of the results of the monthly analyses of the London Waters, made by Dr.Letheby and Dr. Tidy, during the last ten years, together with many valuable remarks on the sources of supply of the different companies, and the variations in the character of the Waters. The main object which the author has had in view has been to furnish a compre- hensive book of reference, to enable a fair judgment to be formed on the schemes now before Parliament, for changing the character of the Water Supply of London.With this end in view, he very rightly denounces the extravagant pictures of river pollution, which are from time to time drawn, and endeavours to reduce the whole matter to a more common sense point of view. Be far as his book goes, we think he has acquitted himself well of his task.We wish there had been more information on some points. The microscopical examination of a water is often of such paramount importance that a column in every analysis may be justly devoted to it, and the physical characteristics alone are sometimes enough to condemn a water ; but in this book the information on both is deficient. With these exceptions the book merits full circulation, and better still, full consideration by those who are proposing fresh expenditure.Omega’s pamphlet is of a different style, although written ostensibly for the purpose of giving information in reference to the same question. Some three-fourthe of it consists o f reprints and abstracts of Dr. Frankland’s 1( figures and statements,” in reference to the London Water Supply. Naturally the author starts by referring to the sensational paragraphs, which describe the London Supply as (‘ diluted sewage,” &c., &c.He then goes on to enquire how it was, that if, as Dr. Prankland states, the Thames was in December, 1876, and January, 1877, (( laden with organic matters of the most objectionable origin, which carried down to the intakes of the Metropolitan Water Companies, passed t-hrough the filters and were distributed to the consumers,” the worst water distributed by any of the Thames Companies during the last two years, contained only one part of organic impurity in 175,000 parts of water.Eurther pungent criticisims of the same kind follow. The pamphlet is carefully and cleverly written.Mr. R. Edge, Manchester, writes us a long letter (for which we regret that we have not space pointing out the extent to which milkmen are in the hands of farmers, and suggesting that additionA power should be given to inspectors to take samples from the farmers’ churns, without the intervention of the milkmen in the matter. W h y do not the Manchester milkmen form an association for looking after the farmers, as their London confrdres have done ? Mr.W. (3. Crook has been appointed public analyst for Norwich. Mr. James Napier has been appointed public analyst for West Suffolk. Dr. T. S. Robson han been appointed public analyst for Hartlepool. Mr. M. 0. Hehner, has been appointed public analyst for Ryde. Churchill, t Simpkin.THE ANALYST. 243 COMPOSITION OF THE ASH OF CANE SUGAR. AN analyeis, by Dr. Wallace, of the ash of sugar obtained from canes grown near the sea-coast in Demerara, has recently been published. The following were the results obtained :- Per cent. - - 23.10 Potash - 1.94 Soda Lime 16.10 Magnesia - 3.76 Sulphuric anhydride - 23.76 Phosphoric acid - 5.69 Chlorine - 4.15 Carbonic acid - 4.06 Peroxide of iron - 0.55 Alumina - 0.65 Silica - 12.38 - - - - - - - - - - 101.03 Deduct oxygen = chlorine 0.93 100.10 ~

ISSN:0003-2654    

DOI:10.1039/AN8780300242

出版商:RSC    

年代:1878

数据来源: RSC

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THE ANALYST. 243 LAW REPORTS. At the Borough Police-court, Salford, before Sir John Ilee Nantell, Mary Moss, grocer and proPision dealer, carrying on business at 76, Ordsall-lane, Salford, waa summoned for selling adulterated butter. The Town Clerk (Mr. C. Moorhouse) appeared for the prosecution, and Mr. J. B. Edge, barrister, for the defence. The Town Clerk said that the inspector went to the defendant’s shop on February 18, and asked Mrs.Moss for a pound and a half of butter. H e asked for that which was in the shop and marked 10d. per lb. He told the defendant that he had purchased the butter for the purpose of being analysed, and divided the sample in the usual way. On the butter being analysed, it was found to be mixed with common fat, and was, in fact, what was commonly called ‘ butterine.” There waa no ticket or mark upon the butter, except the ticket, 10d.per lb.” Yr. J. Carter Bell, public analyst for Salford, said he received from the inspector the sample of butter he The inspector was supplied, and paid 1s. ,?d.244 THE ANALYST. purchased, and on analysing it found it contained 80 per cent. of foreign fat. It was, in fact, butterine of the ordinary class.Butterine is made from animal fat-such as beef fat and mutton fat. Sir John : Then adulterated butter is not butterine 3 Witness : They mix a little butter with it. Sir John a Is there any prescribed limit when it is called butter and when it is called ‘( butterine ’’ 3 Witness : Not that I know of. I should not look upon, say 20 per cent. of foreign fat, as butterine. Sir John : To say that the article sold was I‘ to the prejudice of the buyer,” it must be proved that he was supplied with a worse class of butter than he asked for, and that it was deleterious.Witness : Butterine is not deleterious. Mr. Edge : Have you read the opinion of Mr. Estcourt, the public analyst for the city of Manchester, on butter and butterine ? Witness : No.Mr. Edge : Then I will read it to you. I n a lecture delivered at the Broughton College on December 14 last, Mr. Estcourt said :-‘( He regarded the introduction of butterine as a great boon to the working classes, it having to some extent prevented an increase in the price of butter ; and he was of opinion that if the prejudice against imitation could be removed it would be largely used, as it was preferabfe to two-thirds of the salt butter sold.’’ Witness had not heard of that before.He had heard that animal fat is used by the working-classes in lieu of bntter, and he thought there was nothing prejudical to health in butterinc. Sir John Mantell asked the Town Clerk if he thought it necessary to put in evidence as to the price of butter.They all knew that pure butter could not be bought at 10d. per lb. I am convinced that the article was not adulterated. It was sold as butterine, not as butter, It is quite true that it was not sold as pure butter, and the price of pure butter was not paid for it. HEAVY PENALTY FOR ADULTERATIX~ GIN.-Wlliatu Clement, of the Saracen’s Head, Broad-street, Bath, waa summoned for selling, on the 27th Feb., to Inspector Montague, three quarterns of gin, not of the nature, substance, and quality demanded.Mr. H. R. Hodson, barrister, instructed by Mr. F. H. Moger, clerk to the Urban Sanitary Authority, appeared to prosecute, and Mr. J. K. Bartrum was for the defendant. Mr. Hodson having opened the case, called Inspector Montague, who deposed to purchwing the gin.E e asked the barmaid if it was the best gin, and she replied (‘ Yes.” He paid 5d. a quartern for the gin, being 1s. 3d. for the whole. This was the usual price. He offered to divide the gin but it was refused, and he then took it to Mr. Gatehouse, subsequently receiving a certificate of analysis from him. The certihate of the analyst stated the gin to be 46 per cent. under proof, and that it contained 29 per cent.of added water. The percentage of alcohol was by weight 24, water 76. Solids per cent., 0.062. Witness heard that 1? per cent. under proof was the standard for best gin, and 22 under proof for second quality. I t wasserved from a quart bottle. Had paid the same price for gin at Mr. Carter’a bar, which WM only 22 per cent. under proof. Had also bought gin at the same price of Mr.Worthy Baker, of Walcott-street, which was 23 under proof. I n addressing the Bench, Mr. Bartrum said he should show that the cost price of the gin was 12s. per gallon, and it was retailed at nearly the same price. It was therefore absurd to suppose it was precisely the same. H e was told there was one instance in which it was retailed a t 22 per cent.under proof, viz., by Mr. Cater. They knew that Mr. Cater conducted his business in a very handsome manner, and this was one of the inetances in which the public were well served by him. But because Mr, Cater made 80 small a profit upon gin they must not place his gigantic busineas on a par with Mr. Clementa. Gin never was sent out by the merchants of greater strength than 17 under proof.He ventured to say that no publican in Bath-excepting Mr. Cater, who was a glorious exception-retailed gin of a greater strength than 38 per cent. under proof. That was the strength Mr. Clement sold his at, but unknown to him this had been made 8 per cent. more than that under proof, The defendant was then aworn, and said he gave 12s. per gallon for gin (Burnett’s), and after blending it sold it at 4s.per gallon profit. H e added a quart of water to a gallon of gin. After consulting together in private the chairman said the Bench had considered the circumstances, and in the interest of the public, felt it their duty to impose a severe sentence. They ordered defendant to pay a fine of 3310 and the costs, including couniel’a fee, which was fixed at two guineas. SUXDAY MILx.--John W.Hunt, of 46, King Street, Woolwich, was summoned by order of the Local Board of Health for selling adulterated milk. Mr. FarnReld appeared to prosecute, Mr. Carty, inspector, said that on Sunday morning, the 3rd of March, he sent a lad, to buy milk. The analyst oertiaed it to contain 14 per cent. of water. Defendant said he bought the milk from Mr.Sanders, who purchased it from London on account of being extra buey. It W ~ E the Sunday before Shrove Tuesday, The Town Clerk: I think not. Sir John: Then I think the case cannot go further.THE AXALYST. 295 Mrs. Sanders said it was bought in London on Saturday night. Fined 20s. John Fisher, of 2, Upper Woodland Terrace, Charlton, was similarly charged. Mr. Whale defended.Mr. J. Carty, inspector, said defendant was a cowkeeper. On Sunday morning, the 3rd. inst., he requested a lad to purchase milk from defendant in Prospect Row. The lad asked for a pint and a half, and paid 3d. The analyst’s certificate showed the milk to contain not less than 18 per cent. of added water. On a previous occasion defendant’s milk had been found genuine, but that milk was not bought on Sunday. The Board had ordered wit- to purchase samples on Sunday in consequence of complaints. Mr Whale raised a technical objection, that the person who bought the milk did not inform the vendor that it was for analysis.Mr. Slade over-ruled the objection. Mr. Whale urged in mitigation that defendant bought the milk at East Greenwich. Defendant swore to this, and said the Charlton inspector had frequently before taken samples of his milk.Mr. Slade fined the defendant 20s. George Piper, of 21, Prospect Place, was eommoned for a similar offence. Mr. Carty said defendant was a milk-seller. On the 3rd. inst. he sent a lad in for milk, which was reported by the analyst to contain 25 per cent. of water. Defendant said he sold the milk as he bought it. Mr. Carty said the defendant had an inscription on his house L ( Pure milk sold here, 4d. a quart.” Mrs. Saunders said she got the milk from London. Defendant said it would have taken him a week to ascertain if the milk were pure. Mrs. Sanders said this milk was bought from a different person to that supplied to Hunt. This being a first offence, the penalty of 20s. was imposed in this case also, Mr. Slade remarking that as dealers could protect themselves by taking a written guarantee from the persons who supplied them, they would be more seriously dealt with in future.-Ke’entish bdependent.

ISSN:0003-2654    

DOI:10.1039/AN878030243b

出版商:RSC    

年代:1878

数据来源: RSC