摘要:

NOVEMBER, 1906. Vol. XXXI., No. 368. THE ANALYST. THE ESTIMATION OF COCOANUT OIL IN BUTTER-FAT, BY F. W. HARRIS, F.I.C. DURING the past twelve months a considerable amount of experimental work has been done in my laboratory, with the object of testing the utility and reliability of the different methods for the detection and estimation of cocoanut oil in butter-fat. The question has of late years become one of importance from a Public Analyst's point of view, eepecially as cocoanut oil is now placed upon the market devoid of odour and practically neutral. At the outset experiments were made with the Bomer phytosterin acetate test.'K * Zeit. fii5' Untersuch. der iVahr. zcnd Gentusmittel, 1904, vii., 577.354 THE ANALYSTo The cholesterin from butter was purified by recrystallization and examined under the microscope, after which it was converted into the acetate, and after five recrystallizations the melting-point determined. The highest melting-point of the cholesterin acetate obtained from eight different samples was 1 1 5 4 O C.(corrected). As is well known, animal fats contain cholesterin, vegetable oils phytosterin ; therefore the Bomer process, whilst affording unmistakable evidence of the admixture of vegetable oils with animal fats, cannot be employed as a means of differentiating between the adulteration of butter with cocoanut oil on the one hand and rnargarin on the other, as margarine almost invariably contains a vegetable oil as one of its constituents. If by some other method the addition of cocoanut oil to butter is indicated, then the Bomer process, when used as a confirmatory test, is of great value, and if the proportion of cocoanut oil is relatively small, the confirmation by the Bomer process becomes essential.The time occupied in carrying out this process, together with the large quanti- ties of ether necessary, as well as the fact that at least 50 grams of the butter must be taken, precludes the possibility of this process being utilized in any other way than as a confirmatory test. JUCKENACK AND PASTERNACK’S METHOD,* Juckenack and Pasternack have published a method, or, more correctly, a line of reasoning, by which, from a consideration of the relationship between the Koetts- torfer and Reichert-Meissl values, the presence of cocoanut oil in a sample of butter may be determined. I t is well known that the Koettstorfer and Reichert-Meissl values of butter vary in almost direct proportion to one another.I n other words, the variation of these values in genuine butter is dependent upon the fluctuations in the proportion of volatile fatty acids. Juckenack and Pasternack on this basis propose to subtract from the Koetts- torfer value the arbitrary number 200, and the product thus obtained is then deducted from the Reichert-Meissl number. The formula is, therefore : Reichert-Meissl- (Koettstorfer. value - 200). The figure thus arrived at they designate as For genuine butters this ‘‘ difference value ” must be near =t= 0. difference,” and accordingly the value is a positive or negative + or - ‘( difference.” In a margarine prepared without the addition of cocoanut oil the proportion of volatile acids present is relatively very small, whilst the Koettstorfer value differs but slightly from 195, so that the addition of margarine to butter would not seriously alter Juckenack and Pasternack’s value.On the other hand, cocoanut oil has a Reichert-Meissl value of about 7, and a Koettstorfer value of about 255; therefore the (‘difference value ” of cocoanut oil becomes - 47 compared with 0 for butter. * Zeit. fiir Unterszcch. der Nahr. uncl Genusswzittel, 1904, vii., 193.THE ANALYST. 355 The margin between these figures being considerable, it appeared to me likely Obviously, the first essential in deciding the reliability of this process is to With this The samples represented Dutch, to afford a ready means for indicating the presence of cocoanut oil in butter.determine the variations in the ‘‘ difference value ” of genuine butters. object, I examined seventy samples of butter. colonial, and home produce, and the results obtained are summarized as follows : Kumber of Samples. 4 ... ... 5 ... ... 7 ... ... 5 .,. ... 10 ... *.. 20 ... ... 9 ... ... 4 ... ... 2 ... ... 2 ... ... 2 .., ... “ Difference Value.” -4.6 and -4.9 Between -. 4 and - 3 Between - 3 and - 2 - 2.0 and - 1 -1 a n d - 0 0 and +1 +I and + 2 + 2 a n d + 3 + 3 and + 4 + 4 a n d + 5 +5 a n d + 6 The genuineness of these samples was determined by the Reichert-Meissl number, Koettstorfer value, refractive index, and Polenske number, and in two or three doubtful cases was confirmed by the Bomer process.Test samples of butter were prepared, containing 5, 10, and 15 per cent. of cocoanut oil, and the analysis of these yielded the following results : Samples. “ Difference Value. ” Original butter ... ... ... ... ... + 0.5 Original cocoanut oil ... ... ..* ... ... - 53.0 Test sample with 5 per cent. cocoanut oil ... ... - 1.92 9 , ,, 10 ... ... - 4.9 9 7 15 ... ... - 7.2 The fluctuations in the ‘( difference value” of the above seventy butters is therefore from - 4-9 to +6. Juckenack and Pasternack found the fluctuations to be between - 3.5 and +4*25 for genuiqe butters. It will be observed that out of the seventy samples five gave a (‘difference value ” of from -3 to -4, whilst in the case of four samples the value lay between - 4-6 and - 4.9, figures identical with the test sample containing 10 per cent.cocoa- nut oil. In sixteen-practically 23 per cent. of the samples-the negative “ difference value ” was greater than - 2 ; that is, greater than the negative ‘( difference value ” of the test sample containing 5 per cent. of cocoanut oil. It is therefore obvious that this method is useless to indicate with any certainty the presence of less than 15 per cent. of cocoanut oil. 9 1 ? 7 Y ? I ? 7 , METHODS OF POLENSKE, KIRSCHNER, ETC. During the last two years several methods have been proposed for the estima- tion of cocoanut oil in butter, based on the following principles : Firstly, that whereas the predominant constituent of the volatile acids of butter is butyric-caproic, caprylic, and capric acids being present in small quantities-the356 THE ANALYST.volatile acids of cocoanut oil consist principally of caprylic acid, the quantity of caproic acid being very small, whilst butyric acid is entirely absent.” Secondly, that whereas by far the greater proportion of the volatile acids of butter-fat are soluble in water, the reverse holds good for the volatile acid of cocoa- nut oil. Two methods have been proposed by Jensen and Kirschner,i in which the insolubility of the silver salt of caprylic acid is made use of. Kirschner’s method, which is really a modification of Jensen’s method, consists of obtaining a distillate of the volatile acids as in the determination of the Reichert-Meissl value. One hundred C.C. of the filtered distillate are titrated with Fq baryta, using phenolphthalein as indicator.To the thus neutralized solution, 0.5 gram of silver sulphate is added, the flask stoppered, well shaken, and allowed to stand one hour. The solution is then filtered, and to 100 C.C. of the filtrate are added 35 C.C. of water, 10 C.C. of dilute sulphuric acid, and distilled; 110 C.C. are distilled off: this should occupy one hour. The distillate is filtered, and the 100 C.C. of the filtrate titrated as before, This figure, after calculating to 5 grams of the sample, Kirschner designates as the ( ( Neue Zahl ” (new (‘ Butter Number ”). Several estimations were made with this method, but the results were unsatis- factory, probably partly from the fact that, whereas the first distillation is carried out in thirty minutes, the second distillation, according to Kirschner, should take one hour.One point suggested by Kirschner can be utilized in conjunction with the ordinary Reichert-Meissl Number process as a qualitative test for cocoanut oil. He suggests that the remaining 10 C.C. of the original distillate be filtered, and a few drops of a concentrated silver salt solution be added. I n the presence of cocoanut oil a milky solution results, Pure butter yields a clear solution, whilst margarine gives a slightly opalescent solution. A. Muntz and H. Coudon (the ANALYST, 1905, 155) and Polenske: have suggested methods based upon the difference between the ratio of soluble and insoluble volatile acids in butter and cocoanut oil. POLENSKE’S METHOD. $ I have subjected Polenske’s method to a careful and extensive examination.The process, together with the details of the apparatus, etc., have been published in the ANALYST, and are incorporated in the new edition of Lewkowitsch’s Fats and Oils,” vol. ii. It mill therefore be unnecessary for me to enter into any details of the modus operandi. RATIO BETWEEN THE REICHERT-MEISSL NUMBER AND THE POLENSKE NUMBER. Polenske, in his original paper, gives the resuIts obtained by the analyses of thirty-one samples of butter. The Reichert-Meissl number of these thirty-one samples ranged from 23.3 C.C. to 30.1 c.c., whilst the Polenske number correspondingly ’‘ Zeit. f i i y hr’ztersuch. der Xalzr. und Gentismittel, 1905, ix., 65, t Ibid. $ Ibid. Ibicl., 1904, vii., 273.THE ANALYST. 357 fluctuated between 1.5 C.C.and 3 C.C. From the results obtained, Polenske concludes that the Polenske number of genuine butters-that is, the proportion of insoluble volatile acids-increases proportionately with the Reichert-Meissl number. The results tabulated by Polenske do not, however, justify this conclusion, as the following figures, taken from his original paper, indicate : Table I. (Polenske number was given by batters with the Reichert-Meissl number.) Polenske Number. 1.5 1.6 1.7 1.8 1-9 2-2 2.5 Reichert-Meissl Number. 22.5 23.4 23.3 24.5 24.8 25.1 25.2 23.6 24.7 24.8 25.6 25.4 25.0 25.3 266 25.4 26.2 26.5 254 26.2 26.5 26.9 27.5 27.8 28.8 28.8 29.5 I found, by the examination of seventy samples of butter, that the variations in the ratio between the Reichert-Meissl number and the Polenske number was greater than is indicated in the above table. My results may be summarized as follows : Table II.Reichert-Meissl Number. 23 to 24 C.C. 24 9 , 25 ,, 25 7, 26 I 9 30 7 , 31 9 7 31 7 , 32 1 , 33 ,, 32.5,, Polenskc Rumber. 1.3 to 1.5 C.C. 1.4 ?, 2.2 ,, 1.6 ,, 2-3 ,, 1.9 ,, 2.6 ,, 2.5 ,, 2.9 ,, 2.4 ,, 2.9 ,, 2.5 ,, 3.0 ,, 2.4 ,, 3.3 ,, 2.4 ,7 3.3 ,, 2.6 ,, 3.5 ,, The figures in this table indicate that, in a broad sense, a certain relationship exists between the Reichert-Meissl and the Polenske numbers, but that the Polenske number of genuine butters increases in direct proportion to the increase in the Reichert-Meissl number, as concluded by Polenske, is certainly not borne out. No doubt these discrepancies in the ratio between the Reichert-Meissl number and the Polenske number are attributable to the various influences, both natural and artificial, which affect the total quantity, and probably also the ratio of the constituents of the volatile fatty acids of butter.ACCURACY OF THE PROCESS. The essential point, as I found out by experience, to obtain concordant and reliable results by this method is that the size and quantity of the pumice-stone added to promote regular ebullition should be strictly in accordance with the recommendation of Polenske. The caprylic and cstpric acids, being insoluble in water, necessarily float on the358 THE ANALYST, surface of the liquid in the distillation flask, and, consequently, the proportion of those acids which distil over is dependent, other conditions being equal, on the state of ebullition, whether regular or spasmodic.Regular ebullition insures that the fatty layer is thoroughly disintegrated and brought into intimate contact with the water vapour as it rises through the liquid. I n my first estimations I employed three or four pieces of pumice-stone of about 1.5 em. diameter. The results obtained were much below those obtained by Polenske. After careful revision of the measurement of the tlpparatus, rate of distillation, and generally the mdus o p e r a d , the same low figures resulted. On again reading Polenske's original paper, I found that he recommended the use of powdered pumice- stone in quantity sufficient to cover the point of a pocket-knife blade. On repeating the estimations with this quantity of powdered pumice-stone, the results were satisfactory, duplicate estimations agreeing very closely.I n view of these results, I made a series of experiments to ascertain the extent of the effect different sizes and quantities of pumice-stone would have on the results. I found that the quantity of powdered pumice-stone recommended by Polenske was approximately equal to 0.1 gram; therefore this quantity was rigidly adhered to. The results I obtained with different sizes of pumice-stone are as follows : Three Pieces of Pumice-stone about 1.5 cm. Table 1II. 0.1 Gram of Powdered Pumice-stone. Reichert-Meissl Number.. 24.8 26.8 28.2 28.2 28.3 28.6 28-7 30.8 Polenske Number. 1.4 1.5 1.5 1.8 2.1 1.8 1.8 2.1 Reichert -11eiss1 Number. 24.8 27.4 28.6 28.8 28.6 28.7 29.2 31.3 Polenske Number. 2.2 2.5 2.4 2.5 2.9 2.9 2.9 2.55 By the use of 0.1 gram of pumice-stone the ebullition was very regular and the fatty layer thoroughly disintegrated.After making a considerable number of estimations in duplicate, I was convinced that, provided the conditions as specified by Polenske are rigidly adhered to, the results obtained are thoroughly reliable and concordant. As an example, I tabulate the results obtained by duplicate estimations of two samples of butter which were reported upon as containing cocoanut oil : Table IT? Reichert-Meissl Polenske Number. Numb cr. First estimation ... 324 4.0 No' '{Second estimation ., . 32.1 4.0 First estimation ... 31.0 4.1 No* '{Second estimation . . . 31.0 4.15THE ANALYST. 359 APPLICATION OF THE METHOD FOR THE DETECTION OF ADULTERATION OF BUTTER WITH COCOANUT OIL.In order to ascertain to what extent this method can be depended upon to detect cocoanut oil in butters, mixtures were made containing 5, 10, and 15 per cent. of cocoanut oil. The results are tabulated in the following table : Table V. Reichert- Polenske Koettstorfer ” Difference Meissl Number. Number. Value. Value.” Original butter ... ... ... 32-5 ... 2.55 ... 232.0 ... + 0.50 Test sample, 5 per cent. cocoanut oil 31-0 ... 3-50 ... 232.9 ... - 1-92 9, . . . - 4.90 Test sample, 10 ,, ,, 30.8 4-00 ... 235.7 ... Test sample, 15 ,, 7) ,, 29.9 4-80 237.1 - 7.20 Cocoanut oil ... ... ... ... 7.5 ... 17.60 ... 260.5 ... - 53.00 I t was my intention to extend this series of experiments very considerably, but pressure of work has prevented me.Polenske in his paper stated that his method failed to detect less than 10 per cent.. of cocoanut oil. From his exhaustive results, he concluded that generally an addition of 1 per cent. cocoanut oil increased the Polenske number by 0.1 C.C. He recommends, possibly in order to cover all natural fluctuations in the Polenske number, that before deciding whether a sample contains cocoanut oil or not the Polenske number of the sample be compared with the Polenske number of a pure butter with an equal Reichert-Meissl number. To this latter figure Bolenske adds 0.5 c.c., and if the Polenske number of the sample under consideration is above this increased number, then the presence of cocoanut oil must be assumed; and in calculating the quantity of cocoanut oil present, he subtracts from the ascertained Polenske number of the sample the corresponding Polenske number for a pure butter with an equal Reichert- Meissl number, and by multiplying the product by 10 the percentage of cocoanut oil is arrived at.I n expressing an opinion as’to the value of this method as a means of estimating cocoanut oil in butter without asserting that the addition of 10 per cent. of cocoanut oil could be estimated by this means, I would affirm that, provided a large number of samples of varying Reichert-Meissl numbers have been tested by this method, so as to form a reliable basis of comparison, then it is, in my opinion, quite possible to detect the admixture of 10 per cent. of cocoanut oil with a relative degree of certainty; and an addition of 15 per cent. can not only be detected, but fairly accurately estimated, by the Pdenske method. The fact must not be lost sight of that, by the addition of cocoanut oil to butter, not only is the Polenske number increased, but the Reichert-Meissl number is lowered, certainly to a less extent, but, nevertheless, appreciably ; and, as my table indicates, the lower the Reichert- Meissl number, the lower the maximum Polenske number, and, therefore, the greater the contrast between the increased Polenske number, due to the addition of cocoanut oil, compared with the corresponding maximum number for pure butter.As an example: In Table 11. the Reichert-Meissl number 31 c.c., corresponding to a, maximum Polenske number of 3.3 c.c., the addition of 10 per cent.cocoanut oil ... ... ...360 THE ANALYST. (Reichert-Meissl number, '7.8 ; Polenske number, 17.6) to a butter giving these figures, would give a mixture yielding theoretically the following results : Reichert-Meissl number = 28.6 ; Polenske number = 4.73. If this Polenske number, 4.73, be compared with the maximum numbsr for a Reichert-Meissl number, 28 to 29 (Table II.), which is 2.9 c.c., then we have the maximum Polenske number, 2 9 c.c., compared with 4.73 ; and 4.73 - 2.9 x 10 = 18.3 per cent. cocoanut oil. Employing the maximum Polenske figure (Table 11.) as a basis of calculation, I find that the mixtures of butter and cocoanut oil containing 5 , 10, and 15 per cent. of the latter ingredient, show by this method 2, 7, and 18 per cent.cocoanut oil respectively, results, whilst laying no claim to scientific accuracy, are nevertheless of considerable value. I n addition, the simplicity of the method, and the fact that by one operation both the Polenske and Reichert-Meissl numbers are determined, and that duplicate estimations-if the conditions specified by Polenske are strictly adhered to-agree very dosely, are strong recommendations for the adoption of this method in the routine examination of butter samples. I n conclusion, I must point out that the employment of cocoanut-oil cake as a feeding-stuff, and the influence that such a food-stuff is likely to exert on the analytical data of butter samples, must be considered. Juckenack and Pasternack ': in a recent paper give analytical data obtained by the analysis of butter derived from cows fed on cocoanut-oil cake. Whilst these figures were indicative of the addition of cocoanut oil, the absence of phytosterin was proved by the melting-point of the acetate compound being 113" C. The authors conclude, from their analysis of many thousands of samples, that samples giving such abnormal figures are extremely rare ; still, the possibilities of such figures being obtained with a perfectly genuine butter show the necessity, if the Polenske number is indicative of the addition of cocoanut oil to the extent of 10 per cent. or less, of corroborating the presence of cocoanut oil by the phytosterol acetate test. INSTITUTE OF CHEMISTRY OF GREAT BRITAIN AND IRELAND. EXAMINATIONS IN CHEMICAL TECHNOLOGY. THE first Examinations in Chemical Technology wpre held at the Institute from October 16 to 18, 1906. Three Candidates presented themselves on this occasion for the Examination, one of whom (Mr. James McLeod, F.I.C., Chief Chemist to the Glasgow Corporation Gas Trust) satisfied the Board. * Zeit. fiir Untersuch. der Na7b~. uizd GewussmitteZ, 1906, xi., 156.

ISSN:0003-2654    

DOI:10.1039/AN906310353b

出版商:RSC    

年代:1906

数据来源: RSC

摘要:

THE ANALYST, 361 ABSTRACTS OF PAPERS PUBLISHED IN OTHER JOURNALS. FOODS AND DRUGS ANALYSIS. On the Occurrence of Tannic Acid in Natural -Wines. Jul. Mayer. (Chem. Ztg., 1906, xxx., 898.)-The author states that in his experience all natural wines contain tannic acid. A considerable portion of this may be removed by treat- ment with gelatine, but never the whole. A wine free from tannic acid is to be regarded as a spurious article. A. G. L. Java Olive Oil. K. Wedemeyer. (Zeit. Untersuch. Nahr. Gelzussm., 1906, xii., 210-212.)-The Java olive is the seed of one of the Sterculiaces, and consists of an outer, parchment-like husk enclosing a hard shell, which contains the fleshy part of the seed. The shell yields about 10 per cent. of a yellow, butter-like fat, and the fleshy part 46.6 per cent.of a bright yellow oil, whilst the whole seed (husk, shell, and flesh) yields 30.3 per cent. of oil. This oil from the whole seeds is similar in appearance to ordinary olive oil, has a slightly rancid smell, but an agreeable taste. The following are its chemical and physical constants : Specific gravity at 15" C. ... ... 0.9360 Refractive index at 40' C. ... ... 1.4654 Iodine value ... ... ... ... 76-6 Saponification value ... ... ... 187.9 Free acid ... ... ... ... 2.6 Acetyl value , . . ... ..- ... 23.5 Reichert-Meissl value ... ... ... 0.8 When heated to a temperature of 240' to 245" C., the oil is converted quite suddenly into a gum-like substance, sufficient heat being evolved during the change to carbonize the mass, unless the latter be cooled immediately, This gum-like substance is insoluble in all known solvents, and does not harden when exposed to air and light.The fatty acids separated from the oil behave similarly; when dried at a moderate temperature they become viscous, whilst prolonged heating converts them into a gummy substance. w. P. s. The Phosphorus Content of White of Egg. K. Kaas. (Monatsh. Chem., 1906, xxvii., 403-409.)-The quantity of phosphorus contained in white of egg, as shown by the results of analyses given by the author, varies considerably, and appears to depend on the age of the egg. The albumin of a perfectly fresh egg yielded 0.155 per cent. of phosphorus, whilst that obtained from an egg (laid the next day by the same hen) which had been kept for one month contained 0.228 per cent. Possibly the white of egg withdraws phosphorus compounds gradually from the yolk.As much as 3.06 per cent. of phosphorus was found in crystallized albumin prepared by the Hammersten or Hofman-Pinkus process. w. P. s.362 THE ANALYST. Egg-Yolk preserved with Fluorides. Frabot. (Ann. de Chim. Anal., 1906, vol. 11, p. 330.)-It is stated that for some time past small quantities of fluorides have been found in commercial samples of egg-yolk and broken eggs sold for food purposes. The presence of fluorine was readily detected by drying the samples with the addi- tion of sodium carbonate, igniting the residue, and testing the alkaline ash. It was proved that the normal white or yellow of egg did not contain any natural compound of fluorine. C. A.M. Determination of Crude Fibre in Cocoa Powders. H. Matthes and F. Miiller. (Zezt. Urztersuch. Nahr. Genussm., 1906, xii., 159, 16O.)-The authors employ a slight modification of Konig’s method (ANALYST, 1898, p. 47) for the deter- mination of crude fibre. Five grams of the fat-free cocoa are digested with sulphuric acid and glycerol as described in the original process. After cooling, the mixture is diluted with water and allowed to settle over-night. The clear solution is then decanted on to an asbestos filter, and the residual liquid is mixed with its own volume (about 80 c.c.) of alcohol, and boiled for five minutes before bringing the whole on to the filter. The residue of crude fibre is washed successively with hot water and hot alcohol, then with ether, the asbestos and the residue being next transferred to a platinum basin, dried and weighed.The contents of the basin are finally incinerated, re-weighed, and the weight subtracted from the first weight. The difference gives the amount of crude fibre in the weight of the sample taken. The results obtained by this process are generally from 3 to 4 per cent. lower than those obtained by Konig’s original process; in some cases the difference amounts to over 5 per cent. At the same tims the results are about 0.5 per cent. lower than those yielded by Henneberg’s process. Konig, in a note on the above paper, considers that the slight modification introduced into his method by Matthes and Miiller does not account for the wide difference in the results given by the two methods, and is of opinion that it is due to some other cause.w. P. s. Determination of Crude Fibre in Cocoa. W. Ludwig. (Zeit. Untersuch. Nahv. Genzmm., 1906, xii., 153-159.)-A determination of the amount of crude fibre yielded by a sample of cocoa is recommended as a means of detecting the presence or absence of added husk in the same: two grams of the finely powdered, fat-free cocoa are boiled for fifteen minutes with 20 C.C. of 15 per cent. sodium hydroxide solution and 60 C.C. of water. The mixture is then neutralized with hydrochloric acid, a further quantity of 10 C.C. of hydrochloric acid (specific gravity 1.125) is added, and the whole heated for two hours in a boiling water-bath. The insoluble portion is now collected on a filter, washed with hot water, and then rinsed back into the flask with about 70 C.C.of water ; I gram of anhydrous sodium carbonate is added, the mixture is boiled for fifteen minutes, and filtered. The residue is again rinsed back into the flask with 100 C.C. of water and boiled, with the addition of 5 C.C. of concentrated hydrochloric acid for fifteen minutes, and again filtered. This treat- ment with sodium carbonate and hydrochloric acid ig repeated, the residue obtained finally being collected on a weighed filter, washed with water, alcohol, and ether,THE ANALYST 363 dried and weighed. The filter and its contents are then ignited, and any ash obtained is subtracted from the total weight. Six samples of cocoa powder examined by the author gave from 4.98 to 5.96 per cent. of crude fibre calculated on the fat- free substance, the average amount being 5.60 per cent.These samples contained from 25.05 to 27.92 per cent. of fat. A sample of cocoa husk, containing 3.08 per cent. of fat, yielded 14-47 per cent. of crude fibre after the fat had been removed. h mixture consisting of equal parts of the above-mentioned six cocoas was then made, and to portions of the mixture varying percentages of husk were added. Determinations of the crude fibre in these mixtures gave the following results : Composition of Mixture. Cocoa ... ... ,, 5 per cent. husk ,, 10 per cent. husk ,, 20 per cent, husk ), 40 per cent. husk ,, 60 per cent. husk ,, 80 per cent. husk Fat. Per Cent. ... ... 25-78 ... ... 24.37 ... ... 24.00 ... ... 21-44 ... .. 16.62 ... ... 12.04 ...... 8-26 Crude Fibre in Fat-free Powder. % Found. Calculated. Per Cent. Per Cent. 5.50 5.60 6.03 6.16 6.39 6-71 8.06 7.79 10.18 9.74 11-72 11.48 13-28 13.04 w. P. S. The Pentosan Content of Cocoa and its Value in the Deteetion of Husk in Cocoa Powders. H. Luhrig and A. Segin. (Zed U?ztersz&. Nahr. Genussm., 1906, xii., 161-164.) -Sixteen samples of shelled cocoa beans examined by the authors yielded .from 2.51 to 4.58 (average, 3.34) per cent. of pentosan, calculated on the dry, fat-free substance; whilst eight samples of husk gave from 7.59 to 11.23 (average, 9.26) per cent. of pentosan. From these results it is concluded that the determination is of no great value for the detection of husk in cocoa powder, as considerable quantities of husk may be added to cocoas containing little pentosan without the above limits being exceeded.Tollen's process (ANALYST, 1899, p. 179) was employed for the determinations. w. P. s. Determination of Ergot in Flour, W, Bernhart. (Zeit. Untersuch. Ndzr. Geizussm., 1906, xii., 321-340.)-1n the method described the flour is treated successively with hydrochloric acid, carbon tetrachloride, and ammoniacal copper solution, and the insoluble residue weighed. One hundred grams of the flour are boiled with about 500 C.C. of 2 per cent. hydrochloric acid until the starch is com- pletely inverted, as is shown by testing a drop of the solution with iodine. After being allowed to settle, the clear liquid is poured through dried and weighed silk filter on to which the residue is also brought.This residue is then extracted with carbon tetrachloride to remove fat. The residue is next removed from the filter by the aid of a spatula and placed in a beaker, where it is treated with animoniacal copper solution. The latter must be freshly prepared and of sufficient strength to dissolve cotton-wool readily. When the cellulose present in the residue is dissolved, the mixture is diluted with ten times its volume of water, the residue is again collected on the filter, washed, dried at 100" C., and weighed. The difference364 THE ANALYSTo between the weight of residue obtained from 100 grams of flour containing ergot and the weight of residue yielded by the same amount of flour free from ergot is multiplied by the factor 8.333 to give the percentage of ergot in the sample under examination.If corn-cockle (Agrostemma githago) be present the ergot will be over-estimated by the above process. I n this case the sample is boiled for two hours with 5 per cent. hydrochloric acid, filtered, the residue is boiled for one hour with 3 per cent. sodium hydroxide solution, and the insoluble portion separated and dissolved in concentrated hydrochloric acid. The solution is diluted with fifty times its volume of ice-water and kept in a cold place for several days. The chitine gradually separates out, forming a voluminous white precipitate, which is collected on an asbestos filter, dried and weighed. The weight of the precipitate multiplied by 43.38 gives the quantity of ergot in the portion of the sample taken for the analysis. The method gives approximately accurate results.w. P. s. The Quantity of Solanine in Potatoes. M. Wintgen. (Zeit. Untersuch. &Nahr. Genussm., 1906, xii,, 113-123.)-The amount of solanine existing in potatoes varies considerably, different kinds of potatoes yielding widely varying quantities of the glucoside. Twenty-eight samples of sound potatoes, including eleven varieties, yielded from 0.0172 to 0,1059 gram of solanine per kilo; generally, the quantities found were much less than those recorded by previous investigators. Storing the potatoes for a long time, even if germination takes place, does not increase the solanine content, and diseased potatoes were not found to contain more of the glucoside than sound ones. The formation of solanine by bacteria, as observed by von Weil, could not be established.w. P. s. The Ash of Pimento, Cloves, and Cardamoms. R. Thamm. (Zeit. Uiztersuch. Nab. Gewussm., 1906, xii. 168-172.)--Continuing his work on the analysis of spices (cf. ANALYST, this volume, p. 231), the author now gives the results of the examination of various samples of pimento, cloves, and cardamoms. Nine samples of pimento gave the following results, the figures representing percentages on the dry, sand-free substance : Alkalinity of Ash : C.C. h' Acid per 100 Grams. Ash. Water Water Water Water Total. Soluble. Insoluble. r A -7 r - Soluble. Insoluble. Total. Average ... 4.56 2.58 1.98 68.9 25.3 43.5 Highest ... 4-86 2.80 2-31 74.6 27'9 49.8 Lowest ,s. 4.25 2-25 1.58 63.0 23.3 31.9 Average ... 6-54 3-66 2-88 97.5 37.7 59 -8 Highest ... 6.82 3.76 3.19 104.9 39.7 65 -6 Lowest ... 6-29 3-56 2.62 94*4 32.9 56.2 Six samples of cloves yielded : Two samples of cardamoms (whole fruit) ground by the author gave : 1 ... ... 7.08 4.46 2.62 67.2 11.2 56.0 2 ... ... 3-33 1.10 2.23 50.5 6-6 43.9 w. P. s.THE ANALYST. 365 Oil of Sandalwood. A. R. L. Dohme and H. Englehardt. (Amer. Druggist; through Pharm. Journ., 1906, vol. lxxvii., p. 325.)--E”rom the results of the examination of thirteen samples of the oil distilled from the wood in the authors’ laboratory, it is concluded that the specific gravity of the oil should lie between the limits 0.965 and 0.980 at 25O C., that the quantity of santslol should be from 91 to 92 per cent., and that the oil should be perfectly soluble in, at most, five volumes of 70 per cent. alcohol at a temperature of 25” C. The yield of oil obtained from the different parcels of wood varied from 3.95 to 6-18 per cent, w. P. s.

ISSN:0003-2654    

DOI:10.1039/AN9063100361

出版商:RSC    

年代:1906

数据来源: RSC

摘要:

THE ANALYST. 365 ORGANIC ANALYSIS. A New Method of Detecting and Determining Methyl Alcohol. E. Voisenet. (BUZZ. Xoc. Chim., 1906, xxxv., 748-760.)-The method is based upon the oxidation of the methyl alcohol and detection of the methylal produced by the violet coloration which it gives with proteids and nitrous compounds (ANALYST, =xi., 30). The yellow and violet colorations given by acetals in this test are really due to the acetaldehyde and formaldehyde respectively formed in the decomposition of the acetals by hydrochloric acid. For the detection of traces of methyl alcohol in ethyl alcohol it is necessary to separate by distillation the oxidation products of the latter (acetaldehyde and ethylal), so as to obtain a fraction in which the violet coloration will not be masked by yellow : A volume of the alcohol corresponding to 10 C.C.of absolute alcohol is diluted to 50 C.C. and treated with 5 grams of powdered potassium bichromate and 30 C.C. of sulphuric acid (1 : 5>, and the mixture shaken and alIowed to stand for an hour at the ordinary temperature. The products of the oxidation are now distilled in a 125 C.C. flask with a short neck, connected with a condenser 4 rnm. in diameter and 30 cm. in length, the distillation being conducted SO as to collect the first 30 C.C. of distillate in an hour. If the oxidation and dis- tillation are properly carried out, the whole of the acetaldehyde derived from the 10 C.C. of absolute alcohol should be present in this first fraction of 30 C.C. On now continuing the distillation, the distillate will cease to give the yellow colour in the test, and the next 20 C.C.passing over should contain the methylal (boiling-point 42" C.), whilst the final fraction will contain the ethylal (boiling-point 104" C.). The method is stated to be capable of detecting 1 part of methyl alcohol in 20,000 parts of ethyl alcohol without any preliminary concentration. The method described above should be followed when the proportion of methyl alcohol lies between 1 : 10 and 1 : 1,000. I n the case of a greater proportion than 1 : 10, the volume of alcohol (corresponding to 10 C.C. of absolute alcohol) is diluted to 100 c.c., and the liquid treated with 10 grams of potassium bichromate and 60 C.C. of sulphuric acid (1 : 5 ) . The products of the oxidation are distilled very slowly, the first 50 C.C.being rejected and the next 20 C.C. collected. For smaller proportions than 1 : 1,000, the volume of alcohol is diluted to 25 c.c., and treated in a 75-C.C. flask with 2 grams of potassium bichromate and 12 C.C. of the sulphuric acid. The first 15 C.C. of distillate (obtained in thirty minutes) are rejected, and the test for methylal applied to the next 10 C.C. When only traces (I: 10,000 or 20,000) are present, it is advisable to reduce the quantity of albumin and nitrous acid used in the test.366 THE ANALYST. A colorimetric determination may be made by this method, the colour scale for comparison being prepared as follows : 10 C.C. of absolute alcohol containing 1 part in 50 of methyl alcohol are oxidized and distilled as above described, and the second fraction of 20 C.C.collected. To 4 C.C. of this fraction are added 1 C.C. of a 10 per cent. solution of albumin and 15 C.C. of hydrochloric acid containing nitrous nitrogen, this giving the maximum in scale. The second tube will contain 2 C.C. of the dis- tillate, 2 c . ~ . of water and the reagents, and €he colour will represent 1 : 100, and so on. The different tubes are kept for about fifteen minutes in water at 50" C., after which the colour in each will have attained its maximum. The colour scale, once prepared, can be kept without alteration for several weeks. C. A. M. Nature of the Starch-Iodine Blue Compound. M. Padoa and B. Savarb. (Gaxxetta, xxxvi., 310; through Natwe, 1906, p. 473, and Pharm. Jozwqz., 1906, vol. Ixxvii., p.305.)-In order to elucidate the nature of the blue compound formed by the action of iodine on starch-paste, the authors have investigated the change in the electrical conductivity of a solution of iodine in potassium iodide caused by the addition of starch in known quantities. The conclusion drawn from the experiments is that the blue substance is an additive compound of iodine, starch, and potassium iodide (or hydrogen iodide) containing the two former constituents in the ratio I : C,H,,O, = 1 : 4. Whilst this opinion supports that of Mylius, recorded some twenty years ago, it is opposed to the more recent view of Kiister that the blue substance is not a, definite compound, but is formed as a result of absorption by the colloid starch. Kiister's contention received support quite recently from the work of Biltz, who showed that basic lanthanum acetate, which resembles starch in its colloidal nature, also produces with iodine an intensely blue substance similar in all respects to that formed from starch.I n this case there is no reason to consider the substance as a definite chemical compound. w. P. s. A New Reagent for the Detection of Meehanieal Wood Pulp. A. Berge. (BUZZ.. Xoc. Chim. BeZg., 1906, xx., 158, 159.)-An acid solution of p-nitraniline is stated to keep indefinitely, and to be a very sensitive reagent for mechanical wood pulp. It is prepared by dissolving 0-2 gram of p-nitraniline in 20 grams of sulphuric acid (66' B.) and 80 grams of water. Paper containing wood pulp is coloured by this solution a shade between orange and brick-red.The coloration is clearly distinguishable on isolated fibres, and the particles of wood can easily be counted under the microscope. A great advantage of this reagent is that it does not give any coloration with unbleached chemical cellulose, unless the boiling has been defective. The orange-red colour can be distinguished in artificial light. C. A. M. Investigation of Celluloid. W. Will. ( Z e d s . angew. Chem., 1906, xix., 1377.)-The author finds that properly made celluloid is a comparatively inert Rubstance, which catches fire only on contact with a flame, and not by friction, concussion, an electric spark, or heating to above 100' C. Celluloid of inferior manufacture, however, will catch fire much more easily--e.g., on being kept in the neighbourhood of the source of warmth of a heated room.Such celluloid has alsoTHE ANALYST. 367 a low temperature of decomposition. Celluloid itself burns quietly without exploding, but both the dust produced in working it and the gases yielded by its decomposition or combustion in an inadequate supply of air may give rise to explosions. The latter gases may also produce poisonous effects from their content of carbon monoxide, nitric oxide, or even hydrogen cyanide, The temperature of decomposition of celluloid was determined by placing 0.1 gram of the sample in small pieces in a stout-walled, loosely corked test-tube. This was then plunged into an oil-bath previously heated to 100" C., after which the temperature was raised at the rate of 5" per ininute until the celluloid decomposed.For the drying of the samples a special doubled-walled oven was used, in which the samples were placed on a tray, which was rotated so as to hasten the drying, the temperature being kept at 110" C. A. G. L. On the Analysis of Celluloid. Hugo Dubovitz. (Chew. Ztg., 1906, xxx., 936.)-Two grams of the finely-divided sample are shaken with 100 C.C. of acetone in a 150-C.C. flask until everything except the ,mineral matter has dissolved. The flask is then made up to the 150-C.C. mark with acetone, and 100 C.C. of the mixed contents transferred to a 100-C.C. flask. To the residual 50 C.C. of solution, 25 of an aqueous 8 per cent. ammonium chloride solution are added, and the whole well shaken, with simultaneous cooling in running water.This treatment yields the nitro-compounds in a coagulated, easily-filtered form, which is not the case if water only is used to separate them from the acetone solution, The precipitate is filtered of3 on a Gooch crucible, first washed with a mixture of 1 part of acetone and 1 part of the ammonium chloride solution to remove the camphor, then with absolute alcohol to remove ammonium chloride, finally dried and weighed. The ash is then determined by adding a little paraffin-wax, and melting it at a temperature below 100" C., after which the crucible is heated cautiously and finally more strongly. The addition of the paraffin-wax prevents detonation. Camphor is determined by subtracting the weight of nitrq-compounds plus ash obtained from the weight of celluloid present in the 50 C.G.of solution. The other 100 C.C. of solution are used in judging the quality of the nitro- compounds present. After precipitating the latter as above with ammonium chloride solution, the precipitate is shaken for thirty minutes in a stoppered 150-C.C. cylinder with 50 C.C. of absolute alcohol; 100 C.C. of ether are then added, and the whole allowed to stand, with occasional shaking, for twelve hours; 50 C.C. of the clear liquid are then evaporated to dryness in a platinum crucible, giving the soluble nitro- cellulose. As a check, soluble nitro-cellulose may also be determined in another part of the solution by precipitating with chloroform, filtering through a linen filter, again dissolving in alcohol and ether, reprecipitating with chloroform, drying at GO" C., and weighing.On another portion of the solution the total N,O, is determined as usual with the nitrometer. The temperature of decomposition is determined by placing the celluloid, cut into pieces, but not filed, in a test-tube in an oil-bath heated to 100" C,, and slowly increasing the temperature. The temperature of decomposition rises markedly with the ash content, as shown in the following table :368 THE ANALYSTc Sample. Camphor. Per Cent. 21.98 35.0 19.6 18.3 32.2 Total Nitro- cellulose. Per Cent. 68.1 64.9 66.7 71.3 67.7 Soluble Nitro- cellulose. Per Cent. 63.77 59.1 - - - NO,. Per Cent. 24.0 23.96 - I __ NO, in the Nitro- cellulose. Per Cent. 35.26 36.78 - Ash. Per Cent. 9.86 0 13.63 10.46 0 Temperature of Decom- position.O c. 136 103 161 131 115 A. G. L. Determination of Picric Acid. E. Feder. (Zeit. Untersuch. Nahr. Ge?tussnz., 1906, xii., 216.)-0 wing to its acid properties, trinitrophenol is capable of liberating iodine from an aqueous solution of potassium iodide and iodate. The trinitrophenol acts as a mono-basic acid, and the quantity of iodine set free is proportional to the amount of trinitrophenol added. The titration of the liberated iodine with thio- sulphate solution, using starch solution as indicator, is quite simple, and the change of colour at the end of the titration is sharp. One C.C. of ?G thiosulphate solution corresponds with 0.0229 gram of trinitrophenol. The latter may also be determined in solutions of its salts by acidifying the same with hydrochloric acid, extracting the mixture with benzene, and evaporating the extract.The residue of trinitrophensl is dissolved in water, and its quantity determined as described above. Aqueous solutions of trinitrophenol may be titrated directly with alkali, using phenolphthalein as indicator? provided that a sufficient quantity of the latter be added. W. P. S. The Use of Chromed Hide Powder in the Analysis of Tannins. E. Nihoul. (Bull. Xoc. Chim. Belg., 1906, xx., 236-240.)-The author has made comparative experiments with samples of chromed hide powder containing 0.6 to 1 per cent. and 4 to 5 per cent, of chromic oxide respectively and a sample of ordinary hide powder a year old, the determinations being made by the standard method. He found that the chromed powder yielded to distilled water only about 2.0 mgms.as against 2.1 mgms. from old ordinary hide powder ; and from this concludes that the latter undergoes profound alterations on keeping, whatever precautions may be used to preserve it. I n further experiments, in which an extract of quebracho, prepared under the standard conditions, was used with 5.5 grams of the different powders, it was found that the hide powder that was only slightly chromed gave an exact result in the determination of the non-tannin matter, whereas the ordinary old hide powder gave a figure more than twice too high, although it was remarkable that the quebracho solution had dissolved less of the soluble substances in this powder than had the distilled water. The results obtained with the highly-chromed powders were also incorrect, and it was found necessary to use at least 12 grams of them to obtain figures in any degree concordant with those yielded with the lightly-chromed powder. Hence the author prefers the use of 5.5 grams of the latter, provided, of course, that the proportion of chromic oxide is sufficient to preserve the hide powder.C. A. M.THE ANALYST. 369 The Quantitative Determination of Carbon Dioxide and of Carbon. John McFarlane and Arnold W. Gregory. (Chem. A ~ w s , 1906, vol. 94, p. 133,) -When small quantities (0.01 gram) of carbon dioxide are to be determined, the error caused by varying condensations of moisture, etc., on the potash bulbs usually employed is considerable, and the authors consequently prefer in such cases to absorb the gas in standard barium hydrate solution, filtering off the barium carbonate formed, and converting it into barium sulphate, which is specially suited to this purpose on account of its relatively high molecular weight.As an additional check, the filtrate from the barium carbonate is titrated with standard acid. In order to avoid the action of the carbon dioxide in the air during the filtration of the baryta solution, the authors make use of the apparatus shown in Fig. 1, which combines the functions of an absorbing and filtering vessel. The wide filter-tube (A) is closed duriog absorption by a piece of rubber tubing and a clip. The filtering medium in it consists of a piece of glass wool covered by a layer of paper or asbestos pulp, kept in place by placing on it a little broken F I G .1. glass. A measured volume of the baryta solution is introduced through B into A after the apparatus has been swept out with pure air ; the gas is then allowed to enter through B, and drives some of the liquid up the spiral tube (C) into the second bulb, the absorption thus being made very efficient. The barium carbonate obtained after washing with boiled-out water is dissolved out of the apparatus with dilute hydrochloric acid, and converted into barium sulphate as usual. If the quantity of barium carbonate is large, filtration is very tedious, on account of the gelatinous nature of the - precipitate, and the authors then recom- mend the use of the apparatus shown in Fig. 2, in which an ammoniacal solution of barium chloride constitutes the absorbing medium.This solution contains 50 grams of barium chloride and 250 C.C. of 0.880 ammonia per litre. The solution is boiled just before use, and filtered hot through the filter-tube (C), provided with a tap, into the first of the two flasks (A), the connecting-tubes being of such a length that a part of the liquid is afterwards driven over into the second flask (B) by the gas itself. At the end of the absorption the flask (A) i E ____- FIG. 2.THE ANALYST* 370 heated until it boils, the steam issuing from it heating (B) sufficiently to precipitate all the barium carbonate in this flask. Both flasks are then allowed to cool, and are then only disconnected and their contents filtered. Practically no precipitation of barium carbonate takes place in cold ammoniacal solutions.The barium carbonate obtained is converted into barium sulphate, as before. The results obtained in this way are good. A. G. L. The Determination of Tannin in Tanning Materials. Boudet. (Bzhll. SOL Chim., 1906, xxxv., 760-762.)-The method is a more exact and simpler modification of that of Jean, and depends on treating the solution of the tannin with an excess of iodine and titrating the uncombined excess by means of standard sodium thiosulphate solu- tion. I t has been found by numerous determinations that 1 gram of iodine combines with 1.137 gram of pure dry tannic acid. The reagent is prepared by dissolving 4 grams of pure dry iodine and 8 grams of potassium iodide in a, litre; whilst the thiosulphate solution contains 7-81 grams per litre, Since 4 grams of iodine should saturate 4 x 1.137 grams of pure tannin, the latter quantity of the sample is dissolved in a litre of water, and 10 C.C.of the solution treated with 10 C.C. of the iodine solu- tion, and allowed to stand for two hours. The excess of iodine is then titrated by means of the thiosulphate solution, and the number of C.C. of iodine solution, less the number of C.C. of thiosulphate solution, gives directly the percentage of pure tannin in the sample. Gallic acid may be determined in the same way, 1 gram of iodine combining with 0.467 gram of that acid. Hence 4 x 0.467 = 1.87 grams of a commercial sample are taken for a determination. I n the case of a mixture of tannic and gallic acids 4.54 grams are taken, and the two acids determined together.The tannin in the solution is then absorbed by means of hide powder and a second determination made of the gallic acid in the filtrate in terms of tannin, which can be corrected into gallic acid by multiplying by the factor 0.41. C. A. M. Measurements of the Temperatures of Gelatinization and of Specifie Gravities of some Glue Solutions. K. Winkelbleeh. (Zeits. afiyew. Chem., 1906, xix., 1260.) -Constant results for the temperatures of gelatinization of glue solutions are obtained by vigorously agitating in a cold water-bath a considerable amount of the solution (400 c.c.) contained in a flask (of 500 C.C. capacity), and noting the point at which a thermometer placed in the glue solution remains stationary for some time. The flask must be well shaken during the cooling, especially if dilute (2 per cent.) solutions are being examined, as otherwise there is a possibility of supercooling.Determinations of the specific gravity at various temperatures by weighing agreed well with results given by the hydrometer, after allowing for the small correc- tion needed, on account of the drawing up of the opaque liquid around the hydro- meter by surface tension. A table giving results obtained for some German glues i s also given. A. G. L. Characteristics of Roasted Copals and of Copals treated with Phenols OF Naphthalene. C. Coffignier. (RzdI. SOC. Chinz., 1906, XXXV., 762-767.)-WhenTHE ANALYST. 371 copals are heated in an autoclave with phenols or naphthalene at a temperature of 260' to 290" C., and at a pressure of 2 to 6 atmospheres, they are rendered, without loss, soluble in a, mixture of linseed-oil and turpentine (French Pat.334,300, October, 1904). The same result is obtained, though with considerable loss, on simply roasting the copals. In order to determine the effect of the two methods upon the general properties of copals, the author has made comparative experiments with Madagascar copaI, and his chief results are as follows : Melting point. Natural Madagascar copal ... ... ?l!I a d a g a s c a r copd, roasted ... ... Mad a ga s c a r copal r e n d e r e d soluble with naphthalene Acid 1-alue. Specific Cirdvity at 16" C. O c. 300 205 165 1.0588 1-062 1.061 93 68.2 68 Saponi- fication Value. 70.1 44.9 65.9 Alcohol. Per Cent 73.8 91.8 74.4 Insoluble in Ether.Per Cent. 65.0 51.8 19.7 Chloroform. Per Cent. 69.0 1.7 soluble Benzene. Per Cent. 75.4 1.5 40.0 Roasted copal is very soluble in oil of turpentine, whereas copal treated with naphthalene is only slightly soluble (about 50 per cent.). On the other hand, copal treated by the naphthalene process is completely soluble in amyl acetate, whilst the roasted copal is only very slightly soluble, Whichever method is employed the acid value is invariably lowered. The specific gravity is somewhat increased, and the melting-point and saponification value greatly lowered. C. A. M. Optical Analysis of Technological Gas Mixtures. F. Haber, (Zeits. angew. Chem., 1906, xix., 1418.)-The author has worked out an entirely new method for the instantaneous examination of a number of gas mixtures, which depends on the - - - - - comparison of the refractive index of the gas mixture with that of a known gas or mixture.I n the figure a diagram of the apparatus used, made by Carl Zeiss, is shown. Light from a lamp (not shown) goes through a prism (I), through the objective of the telescope (Ob), to a, double reflecting prism; thence through the actual gas prism and its envelope (P) to a mirror (Sp), and then back again, an372 THE ANALYST. image of the prism (I) being formed on a real scale (Sk) placed close to (I). This image is viewed through a microscope, the eyepiece of which (k) is at right angles to the objective. If the prism below the eyepiece is removed, the light goes straight on to the left, where a camera or another eyepiece may be placed. The gas to be examined is sent either through the gas prism (P) or else through its envelope, the standard gas being sent through the other vessel. The size of the prism is 20 x 2 x 1 em. I t is made of glass plates cemented to a metal body. The relative refractive index of the two gases is given by the displacement of the image of the prism (I) along the scale. The necessity for the use of a microscope becomes apparent when it is remem- bered that the reEractive indices of gases vary only in the fourth or fifth decimal place. In fact, the gases so far examined fall into seven classes, the individual members of each of which cannot be compared with each other in this way, as their refractive indices are too close together. Each division of the scale is 0.02 mm. distant from the next, and corresponds to a difference in the refractive index of 0.0000015. The instrument is sensitive to about one-fifth of this value. As examples of the application of the method are given the determination of carbon dioxide in air, 1 per cent. of carbon dioxide corresponding to 1.1 scale divisions; the determination of hydrogen or methane in air, both about as accurate as that of carbon dioxide ; and the determination of heavy hydrocarbons or benzene vapour in illuminating gas before and after enrichment, about ten times as sensitive as the foregoing. The author believes it possible to apply the instrument to a, number of other simple technological determinations. A. G. L.

ISSN:0003-2654    

DOI:10.1039/AN9063100365

出版商:RSC    

年代:1906

数据来源: RSC

摘要:

372 THE ANALYST. IN ORGANIC ANALYSIS. The Colorimetric Determination of Small Quantities of Gold. Ralph Nelson Maxson. ( Z e d s . Anorg. Cherm., 1906, xlix., 172.)-Small quantities of gold may be readily determined colorimetrically by dissolving the gold in aqua regia, evaporating the solution to dryness on a water-bath, treating the residue with a small amount of an aqueous solution of acetylene, and comparing the colour of the red colloidal gold solution produced with the colour given by a known amount of a standard gold solution, a Penfield colorirneter being convenient for this purpose. Scrupulous care must be taken to ensure the absence of all electrolytes, which would coagulate the gold ; treatment of the vessels used with steam is recommended. The addition of a few drops of ether also helps to prevent coagulation.If only very small quantities of gold are present, the volume of the solution used should not exceed a few C.C. Gentle warming of the residue before treating with the acetylene solution increases the rapidity of the reduction, but care must be taken that no gold is reduced to the metallic state at this point. As regards the accuracy of the results, the maximum error on quantities of gold of from 0.00080 to 0.00001 gram is about 10 per cent., and very often the error is much less than this. A. G. L. The Separation of Iron and Manganese from Nickel and Cobalt. W. Funk. (Zeit. and. Chem., 1906, xlv., 562-570.)-1n separating nickel and cobalt from iron and manganese by treatment of the precipitated sulphides with dilute acid,THE ANALYST 373 it is preferable to use formic acid instead of the usual hydrochloric or sulphuric acid.But even then the results are not so greatly improved that a single precipitation can yield an exact separation. The method, therefore, cannot be recommended in the case of iron, since the process must be repeated twice at least, and when considerable amounts are present, both the precipitate and filtrate must be treated. For the technical analysis of New Caledonian ores, it is best to separate the iron from the manganese, nickel, and cobalt by the acetate or other method, and then to separate the last three metals. For the separation of manganese from nickel and cobalt a single repetition of the process is sufficient, and it is not necessary to treat the precipitate again, since it will only contain traces of manganese.The following method is recommended : The solution, containing about 0.1 gram of nickel or cobalt in 200 C.C. and 2 per cent. of ammonium chloride or sulphate, is treated with ammonium sulphide in the smallest possible excess, and the precipitate allowed to subside until the liquid cools, A dilute (about normal strength) solution of formic acid is now added until the manganese sulphide has dissolved, and the solution contains about 0.5 to 1.5 per cent. of free acid. The liquid is next saturated in the cold with hydrogen sulphide, being meanwhiIe continually stirred, and the precipitate collected and washed with dilute hydrogen sulphide solution. The filtrate is concen- trated slightly, and the treatment repeated in order to separate the small quantities of nickel and cobalt still remaining in solution.If iron has been separated first by the formate method, this treatment is preferable; but if the acetate method was usea to separate the iron, it is best to precipitate the nickel and cobalt from an acetic acid solution by means of hydrogen sulphide. As regards accuracy, the two methods are- equal. C. A. M. The Influence of Ammonia and Ammonium Salts on the Titration of Zinc by Schaffner’s Method. A. Deckers. (BUZZ. Xoc. Chim. BeZg., 1906, XX., 164-167.)-1t is shown that in titrating zinc with sodium sulphide solution ammonium salts, whether in neutral or ammoniacal solution, decompose the sodium sulphide with the liberation of hydrogen sulphide, and that the amount of the latter produced is proportional to the quantity of ammonium salts present. They have a similar action upon freshly precipitated zinc sulphide, and the intensity of this reaction increases with the proportion of free ammonia.Hence, in order to obtain accurate results by Schaffner’s method it is essential that the solution of the sample and the standard solution for the comparison should not only contain equal amounts of ammonia and ammonium salts, but also that the proportion of those salts should not be too high. C. A. M. The Iodometric Determination of Hydrogen Sulphide. 0. Brunck. (Xeit. anal. C7zem., 1906, xlv., 541-551. )-Direct titration of hydrogen sulphide with iodine solution invariably yields too low results, whether the titration be done in neutral or in alkaline solution.Even when the determination is made very rapidly there is still a considerable loss. Correct results, however, can be obtained by the modification of Fresenius, in which the dilute solution of hydrogen sulphide is run into an insufficient amount of iodine solution, and the titration then completed with374 THE ANALYST, the same iodine solution. If the difference between the amount of iodine solution originally taken and the total amount consumed is considerable (more than 1 C.C. of i& iodine solution) the determination must be repeated, a larger amount of the original iodine solution being used. The method of back titration gives results in agreement with the gravimetric results, whether in a neutral or an alkaline solution.I n the latter case the iodine solution must obviously be rendered acid before the titration with sodium thiosulphate solution. I n the case of strong solutions of hydrogen sulphide, it is advisable to use sodium bicarbonate to prevent loss. Soluble sulphides can also be titrated by these methods, but it must be remembered that in practice solutions of alkali sulphides almost invariably contain thiosulphates. C. A. M. Remarks on the Usual Reactions for Nitric Acid. P. Soltsien. (Phnrm. Ztg., 1906, vol. 51, p. 765 ; through Chem. Ztg., 1906, xxx. [Rep.], 309.)-Nitrous acid not only does not yield the reaction with diphenylamine given by nitric acid, chlorine, and other oxidizing agents, but actually hinders it. I n presence of comparatively large amounts of nitrous acid small quantities of nitric acid may not give the reaction at all.Nitrous acid also interferes with the bromine reaction. A. G. L. Two New Colour Reactions of Nitric Acid. C. Reichard. (Chem. Ztg., 1906, xxx., 790.)--14rbuti?z is coloured intensely yellow by concentrated nitric acid. To carry out the test on the free nitric acid, a drop of it may be added to a little solid arbutin on a white tile. If the acid is too weak, however, no colour is produced in this way. In that case a drop of strong sulphuric acid is added, or, better, the acid is converted into potassium or ammonium nitrate, which is evaporated to dryness, a little arbutin and a drop of sulphuric acid being then added. Nitrates are detected in a similar manner, as little as 0.00015 gram potassium nitrate giving a distinct colour. Hydrochloric acid may be used instead of sulphuric acid, but the mixture then requires warming, and the reaction is not so delicate.On absorbing the coloured solution in filter-paper and treating with alkalis, certain changes are produced. The colour given by hydrochloric acid is turned reddish-yellow by a 40 per cent. solution of potassium hydroxide, while the colour given by sulphuric acid is turned violet (in places only) by ammonia. If a little berberiiz hydrochlornte is treated with a drop of nitric acid, and the mixture warmed till dry, a deep red-brown residue, which may be almost black in places, is obtained. I n the presence of sulphuric acid the colour is produced in the cold with either nitric acid or a nitrate ; 0.00002 gram nitric acid will give a deep colour.If hydrochloric acid is used instead of sulphuric the colour produced is the same, but is only obtained on warming. Acetic acid yields a violet-blue residue. A. G. L. On the Standardization of Iodine and Thioswlphate Solutions. G. Bruhns. (Zeit. Anorg. Chern., 1906, xlix., 277.)-Referring to Metzl’s work on the same subject (ANALYST, 1906, xxxi., 96), the author shows that potassiuni bichromate is a perfectly suitable body for the standardization of thiosulphate solutions. TheTHE ANALYST. 375 only precaution necessary to insure accurate results is that the mixture of bichrornate, hydrochloric acid, and potassium iodide must be allowed to stand (in a closed vessel) for thirty minutes before the titration, in order to allow the reaction to complete itself. Still more convenient for the same purpose is the use of a standard solution of potassium permanganate, which, in the author's experience, can be preserved un- changed for a very long time, the advantage of permanganate over bichromate being that with the former the reaction, which results in the liberation of the iodine, is in st ant an eous .A. G. L. The Volumetric Determination of Sulphuric Acid by Means of Benzidine. E. Lemaire. (Am. de Chim. AnaZ., 1906, vol. 11, pp. 333-335.)-The methods based on the insolubility of benzidine sulphate in cold water haye been studied by the author with special reference to the determination of sulphuric acid in hydrochloric acid, The difference between the results given by the methods of Muller (ANALYST, xxviii., 332) and of Raschig (ANALYST, xxviii., 333) hardly exceed 1 per cent., but a consider-- able error is introduced through the solubility of the benzidine sulphate in hydro- chloric acid.To obviate this it is essential to carry out the titration only after complete neutralization of the acid, and the most accurate results are obtained by working at a temperature of 60" C. In the modification recommended by the author 5 C.C. of the hydrochloric acid under examination are mixed with 100 C.C. of water and a few drops of phenolphthalein solution, and titrated with standard sodium hydroxide solution, the result giving the total acidity. Ten C.C. of the benzidine hydrochloride solution (prepared as described by Raschig) are then added, and the flask shaken and allowed to stand for a few minutes. The precipitate is washed with the aid of the filter-pump and then returned to the Hssk, shaken with water at 60" C., and titrated with & sodium hydroxide solution, with phenolphthalein as indicator.The result is calculated as hydrochloric acid and deducted from the amount of total acid previously determined. The benzidine method has been used with success by von Knorre (ANALYST, xxx., 170)Tin the determination of sulphur in crude pyrites, and the author has tried it upon the residue from roasted pyrites; but in this case the proportion of sulphur to iron is SO small that considerable quantities ol the substance are required, and the method therefore ceases to be practical.C. A. 311. Causes of Error in the Determination of Phosphoric Acid by the Citro- Mechanical ' Method. E. Guerry and E. Toussaint. (BzdZ. SOC. Chim. Be@, 1906, xx., 167-203.)-The presence of silica is a great source of error in the deter- mination of phosphoric acid in phosphates and basic slags by the citric acid method, since it is liable to be precipitated simultaneously; and the authors' experiments show that where accurate results have been obtained hitherto the amount of silica has been small, or it has been kept in solution by the presence of more or less iron. Thus, on adding to the acid solution of a basic slag a certain quantity of an iron salt the phosphoric acid can be precipitated without the silica, although in all exact determinations the silica ought to be eliminated before the precipitation.For technical purposes the following modification is recommended : 2.5 grams of the376 THE ANALYST. sample are boiled for thirty minutes with 100 C.C. of water and 50 C.C. of aqua regia, and the liquid cooled and made up to 250 C.C. To 25 C.C. of this solution are then added 25 C.C. of a solution of ferric chloride (prepared by diluting 100 C.C. of a, 2 per. cent. solution to 500 c.c.), 50 C.C. of water, 30 C.C. of ammonium citrate solution (containing 10 grams of citric acid) and 15 C.C. of ammonia solution (specific gravity 0.91), and the whole mechanically shaken for thirty minutes, and then treated with 50 C.C. of magnesia mixture, which is added drop by drop. After standing for an hour the supernatant liquid is decanted, and the precipitate washed on to the fiIter with a, 10 per cent.solution of ammonia containing 10 per cent. of the citrate solution. I t is next washed on the filter with this liquid once, and finally with dilute ammonia solution, as in the ordinary method. The results thus obtained agree well with those given by the molybdate method. ,%d$phuric Acid Method-A generally applicable method for the determination of phosphoric acid is to treat the material first of all with hot concentrated sulphuric acid, which expels fluorine and renders the silica insoluble. 2-5 grams of the sub- stance are heated with 10 C.C. of sulphuric acid in a Jena glass flask (or in a platinum basin when the sample contains much fluorine) with constant shaking until the appear- ance of fumes of sulphuric acid (which must not be confounded with those of silicon fluoride, which may be given off first). The contents of the flask are allowed to cool, cautiously diluted with water to 100 c.c., then mixed with 25 C.C. of aqua regia, boiled for ten minutes on a sand-bath, cooled, made up to a definite volume, and filtered. From 5 to 10 C.C. of the ferric chloride solution are added to 25 C.C. of the filtrate, in case the treatment with sulphuric acid was insufficient, and the liquid partially neutralized with ammonia, cooled, treated with 30 C.C. of citrate solution, 15 C.C. of ammonia solution, and 35 C.C. of magnesia mixture, and shaken mechanically for thirty minutes, after which the precipitate is allowed to stand for an hour, and then collected on a filter, washed, and ignited. C. A. M.

ISSN:0003-2654    

DOI:10.1039/AN9063100372

出版商:RSC    

年代:1906

数据来源: RSC

摘要:

376 THE ANALYST. APPARATUS. The Production of a High Vaeuum in the Scheibler Desiccator. (Jounz. Amer. Chem Soc., 1906, xxviii., 834 ; through Chem. Ztg., 1906, xxx., Rep., 294.)-The Scheibler desiccator is provided with an exit tube terminating just below the lid, and with a manometer, a8 shown in the figure. Two wash-bottles are inserted between the pump and the desiccator, one empty, to receive any H. C. Gore. water sucked back, the other containing a little water, by means of which the passage of the air from the desiccator can be watched. The desiccator is charged with about 200 C.C. of concentrated sulphuric acid, and also contains a 10-cm. Petri dish filled with ether. As soon as the pump is started the ether evaporates; when no more bubbles pass through the wash-bottle, the tap of the desiccator is closed, and the latter allowed to stand, or agitated gently.By the latter procedureTHE ANALYST. 377 especially a very high degree of exhaustion (0.1 cm. or less) is rapidly obtained. When substances rich in water-e.g., potato starch-are to be dried, some caution appears to be necessary to prevent the water from evaporating so rapidly as to throw the substance about the desiccator. A. G. L. New Zero Adjustment for Chemical Balanees. J. MeDowall. (Chem. News, 1906, vol. xciv., p. 104.)-The ordinary pointer scale of the balance is replaced by a brass frame, in which a scale slides in grooves, as shown in the diagram. At the right-hand bottom corner of the scale is a, projection which extends through the base of the balance case, and engages the screw-thread fitted below the base, and operated by the milled head shown on the right.If, on releasing the balance, the pointer swings, say, a few diviBions further to the right than to the left, the scale is moved in the desired direction by means of the milled head until adjustment is obtained. I n cases where the balance is completely out of adjustment, the usual counterpoising screws are turned to bring the pointer roughly back to the centre of the scale when the balance is released, the exact zero being then obtained by the above-mentioned device. w. P. S. Improved Mayer’s Apparatus for the Evolution of Chlorine. (Zeit. xii., 221-223, Uyztersuch. Nnhr. Genzcssm., 1906).- I n clearing vegetable tissue for microscopical examination, chlorine evolved from hydrochloric acid and cubes of calcium hypochlorite in Mayer’s apparatus is frequently used.Some disadvantages are attached to this apparatus, which have been remedied by slight alterations in its form. These consist of the addition of two glass taps, and doing away with the revolving glass stopper with a side aperture, by means of which the flow of acid was regulated. This, in the new form, is replaced by a rubber stopper, which does not bind with the hypochlorite, and the flow of acid is regulated by the upper tap. The closure of the lower tap effectually seals off the liquid from the __ ________ -- ____ __ solid contents after the liquid has been driven -- __. up into the side-tube. -__- - w. P. s.378 THE ANALYST, I I A New Laboratory Sink.Heinrich Gockel. (Chem. Ztg., 1906, xxx., 755.) -The novelty of the sink 670----- ---_ bi shown in the figure-which 5--- -- - - - - ---- t I I I I I I I I I 0 u? 0 4 J I 1 1 I I may be obtained from the firms, Dr. Heinrich Gockel and Deutsche Ton - und Steinaeugwerke, both of Ber- lin-consists in the lower funnel - shaped part. This enables long vessels, such tts burettes and cylinders, to be readily washed under the tap in a vertical position. The exit-pipe of the sink may be closed by means of a stopper attached to a, chain, and several removable perforated supports are provided, on which large vessels may be placed whilst they are being cooled in the filled sink. The sink will take flasks up to 5 litres and bottles up to 12 litres capacity in this way.A back-plate fitted with a small shelf, as shown, is also provided. The measurements are in mm. A. G. L. Weighing Bottle. Leo F. Guttmann.-This is intended for the drying of a substance in an inert gas, such as hydrogen or nitrogen, in order to determine any volatile con- stituent it may contain. The bottle is made of light glass, and carries a, stopper provided with gas inlet and outlet tubes. The little ground-in stoppers are exceedingly useful in keeping the bottle air- t ight. A similar weighing bottle to the one illustrated in this journal (this vol., p. 276) was invented, Mr. Guttmann says, by himself six years ago. A description of it is given in Jannasch7s ‘‘ Leitfaden der Gewichtsanalyse,” Leipsic, 1902. It is manu- factured and sold by several dealers in chemical apparatus.W. J. S. A Temperature Regulator for Use with the Immersion Refractometer. F. Lowe. (Chem. Zeit., 1906, xxx., 685, 686.)-The apparatus consists of it large vessel for holding water, and in which the beakers containing the solutions to be examined are successively immersed while the readings are being taken. A support, T, is provided for holding the beakers (Fig. 1) whilst the instrument is suspended from the rod, B, which is clamped to the sides of the water-vessel. The mirror, S, is fixed to the arm, A , and moved by the second rod seen in the diagram. In Fig. 2 is shownTHE ANALYST* 379 a larger form of apparatus, in which twelve or more beakers are fixed to the revolving portion, SG, and their contents simultaneously brought to the desired temperature before being examined by the instrument.This form of the apparatus is also 6 E u FIG. 1. FIG. 2. provided with an outflow for the water and a specially devised distributor for the inflowing water, the latter being distributed through the vessel by a number of small pipes, the use of a stirrer being thus rendered unnecessary. w. P. s. A Simple Method for Piercing Glass. P. N. Raikow. (Chenz. Ztg., 1906, xxx., 867.)-Holes of any desired size may be readily made in glass of any thickness up to 4 mm. by piercing the heated glass with a red-hot needle. The needle should be as pointed and as hot as possible; the glass, on the other hand, must not be warmed too much. The best procedure is to heat the needle in a Bunsen flame in such a position that its red-hot point penetrates just outside the Bunson flame; the previously warmed glass is then pushed up against the point and gradually brought into the flame, the needle being at the same time twisted to and fro until it penetrates the softened glass. Before allowing the glass to cool, it should be well covered with soot to prevent cracking. Any number of holes may thus be made in a test-tube or flask, etc. For convenience in handling, the needle may be fused into a glass holder ; an old thermometer forms the best holder for this puimpose, as other glass usually cracks in contact with the steel needle. A. G. L.

ISSN:0003-2654    

DOI:10.1039/AN9063100376

出版商:RSC    

年代:1906

数据来源: RSC

摘要:

380 THE ANALYST. ADULTERATION OF WINE AND SPIRITS. THE following extracts from a Bill to prohibit the use of certain foreign substances in wine, brandy, whisky, and spirits, passed by the Government of the Cape of Good -Hope, will, in view of the recent agitation in this country regarding the sale of brandy, whisky, etc., be read with interest. * * * * * ?I: 5. Unless the context of the Act otherwise requires-“ Wine ” means the product solely of the alcoholic fermentation of the juice or must of fresh grapes. “ Dry wine ” means wine produced by complete fermentation of the sugar contained in the juice or must of the fresh grapes from which it is made. (‘ Sweet w h e ” means wine containing sugar derived from the juice or must of the grapes from which it is made, and not produced from imported raisins.Sparkling wine ” means wine surcharged with carbonic acid gas, and to which cane-sugar and pure wine spirit may or may not have been added, and includes champagne. ‘‘ Pure wine spirit ” means the rectified distillate resulting from the distillation solely of wine or must. ( ( Natural wine ” or “ pure natural wine ” means the product solely of the alcoholic fermentation of the juice or must of fresh grapes without the addition of any foreign substance as here- inafter defined, before, during, or after the making of the same. 6. No person shall sell, advertise, offer, keep, expose, or deliver for sale, whether wholesale or retail, or exchange or authorize, direct or allow the sale, under the name, label, or designation of “natural wine,” or ic pure natural wine,” or ‘‘ natural dry wine,” or “pure natural dry wine,” or ‘‘ natural sweet wine,” or (‘ pure natural sweet wine,” or “ sparkling wine,” any substance except natural wine, natural dry wine, natural sweet wine, or sparkling wine, to which, before, during, or after the making of the same, no foreign substance has been added.7. The term (‘ foreign substance ” used in this Act-(a) Shall include the following and such others as are afterwards made illegal, viz. : Ethers, essential oils, bitter almond, cherry laurel, flavouring substances, alkaloidal substances, compounds of barium, fluorine, magnesium, strontium, bismuth, arsenic, lead, zinc, aluminium, tin, copper, boron, derivatives of naphthol (abrastol, etc.), sulphuric acid, formalin or formaldehyde, salicylic acid, or other antiseptics (except sulphurous oxide as provided for hereinafter) ; glycerine, saccharine, dulcine, sucrovin, starch sugar, invert sugar, cane-sugar (except in the case of champagne), impure spirit containing more than 1 per mille of fuse1 oil, organic or mineral colouring matters, gums, and any mixture containing any of these substances ; but (b) shall not include the following and such others as are afterwards made illegal : (1) Yeast or leaven.(2) Substances, such as isinglass, gelatin, eggs, albumin, Spanish clay, kaolin, or tannin for the purpose of clarification. (3) Common salt, provided that the total amount of chlorine in the wine, calculated as sodium chloride, does not exceed h gram per litre or 35 grains per gallon.(4) Sulphate of lime, metabisulphite of potassium or sulphurous oxide, provided that the total amount of sulphuric oxide, calculated as potassium sulphate, does not exceed 2 grams per litre or 140 grains per gallon. (5) Tartaric acid. (6) Natural products of grape-vine leaves or flowers. (7) Pure wine spirit, pure wine brandy, or spiritTHE ANALYST, 381 distilled from sound wine at not less than 38’ over proof, for the purpose of in- creasing the alcoholic strength to an extent not exceeding 28 per cent. of proof spirit or 16 per cent. of alcohol by volume in the case of dry wines, or 35 per cent. of proof spirit or 20 per cent. of alcohol by volume in the case of sherries, ports, and sweet wines, or 43 per cent. of proof spirit or 25 per cent. of alcohol in the case of imported wines, alcohol in either case being absolute alcohol of specific gravity 0.7938, and measured at the temperature of 60’ of Fahrenheit’s thermometer.8. No person shall sell, etc., any wine to which has been added water, or cane- sugar in quantity exceeding 8 ounces per gallon, or salicylic acid in quantity exceeding 4 ounces per 127 gallons. 9. No person shall sell, advertise, offer, expose, or deliver for sale, whether wholesale or retail, or exchange, or authorize, direct or allow the sale of wine con- taining more than the following quantities of sulphurous oxide, namely : (a) I n the case of dry wine, 14 grains of free and combined sulphurous oxide or 18 grains of free sulphurous oxide per gallon ; and ( b ) in the case of other wines, 25 grains of free and combined sulphurous oxide or 2% grains of free sulphurous oxide per gallon.10. Nothing in this Act shall be deemed to prohibit the sale of any fermented beverage made from fruit or sources other than fresh grapes, if such is correctly designated as to source and fruit it is made from. 11. Unfermented grape-juice to which there has been added any substance the addition of which to wine is prohibited, or hereafter shall be prohibited may, be sold, provided that nothing in this section shall be construed to place any restriction upon the manufacture or sale of temperance beverages or sacramental wine unless these contain more than 3 per cent. of proof spirit. 12. No person shall manufacture or sell under the name of champagne sparkling wine in which the excess of carbonic acid gas arises from direct admixture of the same.13. The flavouring of wine other than natural wine and the colouring thereof by means of pure caramel shall not be deemed to be an offence. 14. BRANDY, WHISKY, AND LIQUEUR. (‘ Brandy ” means the distillate resulting from the distillation solely of (a) wine or must ; (b) must and grape-husks ; (c) grape-husks and water. ‘‘ Pure wine brandy ” means the unrectified distillate resulting from the distillation solely of pure wine or must ; the volatile constituents of which distillate (except water, as provided for in section 15) are derived entirely from the above-named materials, provided that the alcoholic strength of such pure wine brandy be not lower than 25 degrees under proof, and not higher than 22 degrees over proof.“ Pure grape brandy ” or grape brandy means the unrectified distillate resulting from the distillation solely of wine or must with grape-husks, the volatile constituents of which distillate (except water, as provided for in section 15) are derived entirely from the above-named materials, provided that the alcoholic strength of such pure grape brandy be not lower than 25 degrees under proof, and not higher than 12 degrees over-proof. ‘‘ Dop brandy ” means the unrectified distillate resulting from the distillation solely of grape-husks and water, the volatile382 THE ANALYST. constituents of which distillate (except water as provided for in section 15) are derived entirely from the above-named materials, provided that the alcoholic strength of such dop brandy be not lower than 25 degrees under proof.‘( Whisky ” means a spirituous liquor derived from grain. by fermentation and distillation, the volatile constituents of which (except water, as provided for in section 15) are derived solely from the above material. ‘‘ Malt whisky ” means whisky derived solely from malt. (‘ Blended whisky ” means whisky containing not less than 25 per cent. of malt whisky. * * * * 3(- * 16. No person shall sell under the name of ‘(brandy” or “ whisky” any substance except brandy or whisky. 17. The addition to brandy, whisky, or wine spirit of cayenne pepper, tobacco, bluestone, or any substance whose addition is not expressly provided for in this Act shall be deemed a contravention of this Act.18. The flavouring of brandy other than pure wine brandy or grape brandy, or the addition to any class of brandy, for sweetening purposes, of pure cane-sugar previously made into a syrup (provided that the total quantity of sugar so added does not exceed 1+ ounces per gallon), or the colouring of the same by means of pure caramel or by the material derived from the wood of the cask in which it is stored, shall not be deemed an offence against this Act. 19. No person shall sell, offer, expose, or deliver for sale or authorize, direct, or allow the sale of any Colonial brandy unless the bottle or receptacle containing such brandy is marked, branded, or labelled in such manner as legibly to set forth whether such brandy is brandy, pure wine brandy, pure grape brandy, or dop brandy as defined in section 14.20. No person shall sell, offer, keep, expose, or deliver for sale as or under the name of Colonial liqueur any article in the manufacture of which any spirituous liquor other than pure wine spirit or brandy may have been used. 21. No person shall manufacture or sell, etc., under the name of Colonial liqueur any article which has not been manufactured either - (a) by maceration in pure wine spirit, or brandy of fresh or dried fruit, or peels of aromatic plants, leaves, herbs, roots, or seeds, to which extract has been added subsequently a syrup made of pure cane-sugar or honey; or (b) by redistillation of a macerated extract prepared as above, to the resulting distillate of which a syrup made of pure cane- sugar or honey has been added; provided that in no case the alcoholic strength of any liqueur shall be less than 30 per cent.of alcohol by volume. 22. Nothing contained in the preceding section shall be so construed as to prohibit the use of real essence of mint in the manufacture of any liqueur offered or exposed for sale. GENERAL. 23. No person licensed to sell by retail shall sell, etc., wine, brandy, whisky, or liqueur, unless the bottle or other receptacle wherein such wine, brandy, whisky, or liqueur may be contained is marked, labelled, or branded in distinct letters, with the name and address of both the said retail dealer and, if hottled in the Colony, theTHE ANALYST. name and address of the bottler, and in the case of imported wine, brandy, whisky, Qr liqueur, the name and address of the original importer.24. No person shall manufacture or have in his possession for the purpose of sale, or sell, advertise, offer, keep, expose, or deliver for sale, whether wholesale or retail, or authorize, direct, or allow the sale of any recipe or formula whatever for adulterating any wine, brandy, whisky, or liqueur. 25. Time shall be allowed to enable vendors to dispose of any existing stocks which would otherwise be considered as contravening the provisions of this Act. 26. Gives the necessary powers of entry into any vineyard, storeroom, wine- cellar, bonded or free store, etc. 27. Any purchaser of any article of diet provided for in this Act shall be entitled to obtain from any analyst appointed under this Act, on payment to such analyst of the cost thereof, an analysis of such article by such analyst, and to receive from him a certificate of the result of such analysis, provided that nothing herein contained shall be taken to impose upon any such purchaser the necessity to obtain such analysis and certificate before instituting any complaint or proceeding under this Act if he shall have sufficient evidence otherwise.28. Any person in charge of any article of diet referred to in section 26 refusing to allow the amount required for analysis to be taken by the person offering to purchase and authorized as hereinbefore provided shall be guilty of an offence. 29. All the provisions of this Act shall apply to wine, brandy, whisky, and liqueur imported into this Colony. 30. No person shall import into this Colony, for purposes of sale, or sell, offer, or expose for saIe, within this Colony, under any name, label, brand, or designation provided for in this Act, any article of diet provided for in this Act, which is not of the nature, substance and quality of the article designated by such name, label, brand, or designation, or demanded by any person who may purchase the same.31. From and after the taking effect of this Act all articles of diet provided for in this Act, imported as merchandise and landed at any port in this Colony may be subject to examination by the Customs or other officers appointed in that behalf, and samples may, when deemed necessary by such officers, be taken and with all convenient speed be examined by an analyst as aforesaid, and if: upon such analysis, the same shall be found to be in contravention of this Act, the same shall be forfeited and destroyed or otherwise disposed of as the treasurer of the Colony may direct.32. The person acting as analyst in any given case shall furnish a, certificate as may be provided for by regulation of the Governor in Council on the recommendation of the Administering Officer and published in the Governmeizt Gazette. ic. 8 * +% * + 38. (1) Any person who contravenes any of the provisions of this Act, or of any regulations thereunder, shall be guilty of an offence against this Act, and shall be liable to a penalty of not exceeding $20 for a first offence against any such pro- vision, and in default of payment he shall be liable to imprisonment with or384 THE ANALYST, without hard labour for a term not exceeding three months, unless such fine be sooner paid, and for a second or subsequent offence to a penalty not exceeding 650 and in default of payment to imprisonment for any term not exceeding six months with or without hard labour, and for a third offence to a penalty not exceeding 6100 or to imprisonment for any term not exceeding twelve months with or with- out hard labour, or to both such fine and imprisonment ; provided that any violation of the provisions of section 23 shall not be punished by a fine exceeding 65, or in default of payment by imprisonment with or without hard labour for a term exceeding one month. (2) Every person guilty of an oflence against this Act shall, in addition to the penalty imposed, be liable to pay such amount as the Court may award for the costs and expenses incurred in the taking of proceedings against such guilty person, including the expenses incurred by the prosecution in obtaining the analysis. 39. If there be sufficient defence in any prosecution under this Act for the accused to prove that he had no knowledge of the adulteration complained of, and was not a party to it, he shall be discharged from the prosecution.

ISSN:0003-2654    

DOI:10.1039/AN9063100380

出版商:RSC    

年代:1906

数据来源: RSC

摘要:

384 THE ANALYST, REVIEW a CHEMISTRY FOR DENTAL STUDENTS. By H. CARLTON SMITH, Ph.G. (New York: John Wiley and Sons. London : Chapman and Hall, Ltd. 1906. Pp. viii and 273. As stated in the preface the arrangement of this book follows closely the lecture course in dental chemistry given by the author at the Harvard Dental School. Qualitative and volumetric analysis, dental metallurgy, organic and physiological chemistry, are all dealt with here, in addition to a couple of special sections devoted to digestion and urine. It is hardly necessary to say that with so comprehensive a syllabus each individual subject cannot be adequately discussed within the narrow limits of a treatise of this size. The notes on practical chemistry, given at the com- mencement of the book, are arranged on the lines of the ordinary separation tables, but it would seem hardly necessary to give no less than eighteen diagrams repre- senting filtration by means of a funnel and beaker. The subject of dental metallurgy is discussed in thirty pages, whilst only forty- six are allotted to organic chemistry. I n the latter we notice a curious misprint, HC1, being given as the formula for iodoform. Although possibly the treatise may prove of value to those attending the author’s lectures, it can scarcely be recommended to dental students in this country, where the scope of the examinations in chemistry and metallurgy is of a very different character. P. A. E. R. Price 10s. 6d. net.)

ISSN:0003-2654    

DOI:10.1039/AN9063100384

出版商:RSC    

年代:1906

数据来源: RSC