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Proceedings of the Society of Public Analysts |
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Analyst,
Volume 23,
Issue March,
1898,
Page 57-58
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摘要:
THE ANALYST. MARCH, 1898. PROCEEDINGS OF THE SOCIETY OF PUBLIC ANALYSTS. THE annual meeting was held on Wednesday, February 2, 1898, in the Chemical Society’s Rooms, Burlington House, the President (Dr. Bernard Dyer) occupying the chair. The minutes of the previous meeting were read and confirmed. The following gentlemen were proposed for election. As members : H. H. Dains, F.I.C., 3, Cantonment, Vixianagram, India; A. D. Hall, M.A., Principal of and Professor of Chemistry at the South-Eastern Agricultural College, Wye, near Ashford, Kent ; Otto Rosenheim, Ph.D., 57, Chancery Lane, London ; P. Schidrowitz, Ph.D., 57, Chancery Lane, London. As associates : C. A. Hackman, assistant to Mr. A. C . Chapman; and A. P. Davson, assistant to Mr. Bodmer. Mr. L. K. Boseley was elected a member of the Society, and Mr.F. R. O’Shaughnessy as associate. The RON. TREASUREH. (Mr. E. W. Voelcker), in presenting his report and accounts for the past year, drew attention to the fact that, while the amount of the year’s expenditure was larger than in the case of the previous year, the balance actually standing to the Society’s credit was larger. He was glad to be able to remark that the subscription list was in a more satisfactory condition than it had been in since 1895, there being, as a matter of faot, only five subscriptions remaining in arrear; and he desired to express his appreciation of the kindness with which the members generally had responded to his applications. The chief items in the Society’s expenditure were those connected with the ANALYST, and these items were larger than in the previous year, this being in great measure due to the cost of the General Index which had been published during the year just concluded, and of which the cost of printing alone had been 653. He might observe, however, that the items referring to the ANALYST constituted the only portion of the accounts which showed an increased expenditure over the preceding year, the Society having, in fact, been as economical as possible in every direction, excepting that which, he ventured to say, was the one in which they were right in being lavish in their expenditure.Any surplus money they had to spend, he thought they ought to spend in raising that journal to as high a standard as possible. Mr. JOHN H . B. JENKINS moved the adoption of the report and accounts as58 THE ANALYST. presented by the Hon. Treasurer, at the same time proposing a hearty vote of thanks to the Hon. Treasurer and to the Ron. Auditors (Mr. John Hughes and Mr. Bertram Blount). Mr. EKINS seconded the motion, which was unanimously carried. The HON. TREASURER and Mr. HUGHES responded, the latter saying that the accounts were kept with great accuracy of detail, and in such a clear and admirable manqer that the task of auditing them was a very light one. The President then delivered the following address.
ISSN:0003-2654
DOI:10.1039/AN8982300057
出版商:RSC
年代:1898
数据来源: RSC
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Annual address of the President |
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Analyst,
Volume 23,
Issue March,
1898,
Page 58-66
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PDF (837KB)
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摘要:
58 THE ANALYST. ANNUAL ADDRESS OF THE PRESIDENT. I REGRET to have to begin the remarks I have to make by chronicling the fact that we have lost by death during the past year four of our members. The first name among them is that of our honoured honorary member, Fresenius. His loss has been deplored all over the chemical world; but there is no chemical body or society to whom it comes home with such force as it does to a society which, like our own, is devoted specially to the study and advancement of analysis, the branch of chemical work to which Fresenius devoted his long and fruitful life. His well-known handbooks are among the earliest and best-used possessions of the student, and they are, at the same time, among the most treasured possessions of the most mature analyst among us.Our past-President, Mr. Hehner, who was privileged to be his pupil, has already recorded, much more ably and eloquelstly than I could, in the pages of our journal the appreciation necessarily felt by all analysts of the work of Fresenius and our sorrow at his death; but I nevertheless feel that it would not be becoming to let our annual meeting go by without once again recording our sense of the loss we have all sustained. Mr. F. M. Rimmington, whose loss has also been chronicled in the ANALYST, was one of the oldest members of our Society, and, I think, one of the oldest public analysts in the country; and, although advancing years prevented his taking a very prominent part in the affairs of our Society for some time past, he was formerly active in analytical research, more especially in connection with the examination of drugs. Dr.G. A. Rogers was also an old member of the Society, and an old public analyst, although he had not, I think, for many years taken any active part in our society. Mr. C. H. R. Moore was for a number of years a member of the Society, and for several years previously an associate. He was originally one of my own pupils and assistants, and one for whom I had a deep personal attachment, and his early death has been, as I know, a subject of grief to a number of our members who knew hini as a familiar friend before he left England. A t the time of his death he was working at agricultural chemistry in Jamaica. We have lost during the year by resignation two of our ordinary members, while the names of three members and one associate have fallen out of our list by reason of efflux of time since their last communication with our treasurer.TEE ANALYST. 59 We have thus lost during the year one honorary member, eight ordinary mern: bers, and one associate.We have had, however, the pleasure of adding to our list of honorary members the name of Dr. W. J. Russell, F.R.S., who has earned the thanks of the whole profession for the able way in which for three years he filled the presidential chair of the Institute of Chemistry. Our appreciation of his services in this capacity cannot be better expressed than by saying that he proved himself a worthy successor to Dr. Tilden, with whose name will always be associated what I venture to call the rejuvenescence of the Institute of Chemistry; and we have recorded our sense of Dr.Russell’s services to our profession in the same way as that in which we recorded our recognition of those of his predecessor, Dr. Tilden. This would perhaps be a fitting place to congratulate both our own Society and the Institute of Chemistry upon the fact that Dr. Russell, in resigning his office, has been succeeded by a President no less worthy than our own immediate past- President, Dr. Stevenson, whose hard work in the chair of this Society will be long remembered by all those of us who had to work with him in an official capacity. Under his presidency, we hope to see the Institute holding, in addition to its other examinations, an examination in the much-vexed subject of pharmacology and therapeutics, so as to enable candidates for public analystships to produce evidence of the supplementary qualification in this subject required by the Local Government Board, and thus removing a difficulty frequently experienced.We as chemists have long striven to impress upon the Local Government Board the urgent necessity of a strong chemical qualification for public analysts ; but from the unfortunate frequency with which in the past the Local Government Board has expressed itself satisfied with the qualifications of candidates possessed of medical diplomas, but possessed of very slender chemical qualifications, it would almost appear as though in the eyes of the Local Government Board a therapeutical qualification had sometimes weighed even more heavily than a chemical one.If the Institute of Chemistry is able to see its way, as we now hope that it will, to supplement its already sound and thorough chemical examinations by the pharmacological and therapeutical examination already referred to, it will form a completely qualifying body for the special department of the profession which this Society primarily represents, At one time, in view of the absence anywhere of any examination sufficiently comprehensive and at the same time sufficiently special to test the qualifications of candidates for public analystships, there was on the part of many members of our own Society a wish that we-the Society of Public Analysts-should examine, and grant a diploma. Others of us, however, felt that to further increase the number of examining bodies was exceedingly undesirable, and that this important work was one best reserved for the Institute of Chemistry, which, by its objects, its charter, and its organization, was eminently fitted for carrying out this, among other special as well as general examinations ; and it is satisfactory now to know that such an end to the discussion seems likely to be happily brought about.We have elected during the year ten new ordinary members, while three associates have been transferred to the rank of members. One member who had formally resigned has cancelled his resignation, and four new associates have been added to our list.60 THE ANALYBT. The strength of the Society, as compared with its strength at the close of the two preceding years, is as follows : January, 1896.January, 1897. January, 1898. Honorary members ... ... 10 ... 11 ... 11 Members ... ... ... 210 ... 218 ... 223 Associates ... ... _.. 26 ... 29 ... 31 Total ... ... 246 ... 258 ... 265 I t will be seen that during the past year we have on the whole gained five members and two associates, as compared with a gain of eight members and three associates in the preceding year. Although, however, the Society will be seen to be growing, the growth is too small to be looked upon as satisfactory, having regard to the large enterprise we have held in hand since we enlarged the scope of our journal. I would ask our members to bear in mind that, although our title is a restricted one, our membership is open to any chemist who has the responsible conduct of an analytical laboratory, and I sincerely hope that any member of the Society who has friends who are eligible for our membership, and who are still outside our ranks, will at once impress upon them that to support the only journal in the English language devoted to a comprehensive record of the progress of analytical chemistry is the duty of every member of the profession; and that that support is best given by joining our Society.While, however, I am very earnest in this appeal, I do not wish it to go out as a presidential utterance that we are in actual or immediate need of funds. During our earlier and less ambitious years we accumulated, for a young Society, a not inconsiderable amount of funded property. During the year that has just passed we have not had to trench upon our investments, but I regret to say that we have not been able to add to them.From the treasurer’s statement you will see, indeed, that our income has increased, but you will see as well that our expenses have also increased materially, and it is scarcely necessary to remind you that the great bulk of our income is expended on our journal. Of the activity of our Editorial Committee, and more especially of our able aud energetic Editor, Dr. Sykes, I need scarcely remind you; but I should like to emphasize our work statistically by pointing out that during the year, in addition to 36 original papers, we have published in the pages of the ANALYST no less than 283 abstracts. My predecessor, Dr. Stevenson, was last year at the pains of tabulating the abstracts which we published during 1896, and in order to show the growth of this work I have made a, similar analysis of the abstracts published during 1897, which I now give side by side with his.Abstracts published in t h e ANALYST. 1896. 1897. Food and drug analysis ... ... 55 S6 Toxicologj cal analysis ... ... 9 5 Organic ... ... 86 87 Inorganic ... ... ... ... 86 91 ... Apparatus ... ... ... ... 9 14 Total ... ... 245 283 - -THE ANALYST. 6 1, It will be seen, therefore, that our abstracts were 38 more than in the previous year. We endeavour, as far as possible, to abstract every paper of analytical importance published in any country and in any language, and we are anxious- I speak for the moment on behalf of the Editorial Committee-to make our jaurnal still worthier of the Society; and in order to do this we want two things.As I have already said, we want an enlargement of the membership of the Sdeiety, and we want an increase in the number of original papers read before. the Society. During the past year 34 papers have been read and discussed at our monthly meetings, as against 29 during the previous year ; but I should like to see a much larger record than this, and I should like to see a wider range of analytical subjects. I am afraid that many chemists read or publish elsewhere papers that ought properly t o be read and discussed at our meetings, on account of .our name, which leads them to suppose that the only papers acceptable here are those having to do with subjects falling within the statutory duties of public analysts as such.There cannot be a greater mistake. Even those among us who are primarily public analysts, are, for the most part, in general practice, and are interested, individually or collectively, in the widest possible range of analytical subjects, and any paper on any subject whatsoever connected with analytical chemistry is hear-tjly welcomed at the meetings of our Society. I say this, not for the information of those who axe present, but for the sake of others who are not members of our Society, under whose eyes this address may hll, for I am glad to say that the ANALYST has a large chemical reading public outside of our Society, and it is in the ranks of that chemical reading public that I would fain find more contributors of papers and more recruits for the Society itself.I do not wish, however, on behalf of the Council and officers of the Society, to appear to be in any way ungrateful for the 34 pa.pers read before us during the year, many of which have been most interesting and most valuable to. us, and of which the following is a list : ‘‘ Note on weighing out Fats.” “ A Specific Gravity Pipette.” “ A modified Schmidt Process.’’ “ Some Analyses of Water from an Oyster Fishery.” “ The Composition of Meat-extracts and similar Products.” “ Remarks on Formaldehyde.” “ The Distillation of Formaldehyde from Aqueous Solution.” By Norman ‘‘ The Estimation of Milk-sugar in Milk.” By H. Droop Richmond and L. K. ‘ I The Constitution of Milk.” “ Copper in Preserved Vegetables.” “ Coffee Palace Coffee Infusioiis.” “The Detection of Mixtures of Uiluted, Copdensed, or Sterilized Milk with ‘‘ The Separation and Identification of the Typhoid and Colon Bacilli.” By By Charles E.Cassal. By W. F. Keating Stock. By R. W. Woosnam. By Charles E. Cassal. By Otto Hehner. By Charles E. Cassal. Leonard, B.Sc., Harry M. Smith, and H. Droop Richmond. Boscle y . By EI. Droop Richmond. By R. Bodmer and C. G. Moor, M.A. By E. G. Clayton. Fresh Milk.’.’ F. Wallis Stoddart. By H. Droop Richmond and L. K. Boseley.62 THE ANALYST. L1 Notes on Alcohoi.” “The Value of the Nitrogen Factor in the Analysis of Decomposed Milks.” ‘( Notes on the Influence of Boric Acid upon the Action of Digestive Ferments.” By J. F. Liverseege. By Alfred Smetham. By R. A. Cripps. Note on Heavy Metals in Cheese.” On the Structure of the Fat Globules in Cows’ Milk.” By Professor V.Storch, ‘‘ On Tabarie’s Method for the Estimation of Alcohol.” By Norman Leonard, 1‘ The Determination of Soluble Proteids by Chlorine Precipitation.” By S. ‘1 Note on the Bacteriolysis of Gelatin.” 6‘ Note on Commercial Ground Cassia,” 4 ‘ An Improved Method of Determining Proteid and Gelatinoid Substances.” ‘‘ The Estimation of Acetates in the Presence of Inorganic Salts.” By Bertram “The Estimation of Carbonic Acid in Natural Waters.” By Clarence A. ‘‘ Note on the Graduation of Leffmann-Beam Bottles.” By G. E. Scott-Smith By Alfred H. Allen and F. Hudson Cox. of Copenhagen (communicated by H. Faber). B.Sc., and Harry M. Smith. Rideal, D.Sc., and C. J. Stewart. By S.Rideal, D.Sc., and R. Orchard. By W. F. Keating Stock. By Alfred H. Allen and A. B. Searle. Blount. Seyler, B.Sc. and A. B. Searle. The Detection of Gelatin in Cream.” By Alfred W. Stokes. ‘‘ A new Milk Preservative.” ‘‘ A new Milk Adulterant.” ‘‘ An improved Milk Scale.” By Alfred W. Stokes. By H. Droop Richmond. Milk Analysis and Certification.” A Butter eighteen years old.” By E. G. Clayton. By Alfred W. Stokes. By James Edmunds, M.D. ‘( A Method of Estimating Tannic Acid by means of the Polarimeter.” ‘1 Note on Mineral Matter in Commercial Bleached Ginger.” By E. J. Bevan. As all, or nearly all, of these papers have been actually published in the ANALYST, I need not now linger to review them, but I should like to refer especially to two among them. The first was a paper ‘‘ On the Separation and Identification of the Typhoid and Colon Bacilli,” by Mr.Stoddart. It is gratifying to us as analysts that this, one of the most interesting papers published upon a most important and interesting topic, should have been the work of one of our own members, and a If working public analyst.” I am convinced that those of us who undertake the analysis of water-and what analyst does not ?-will ultimately have one and all to adopt bacteriological methods as supplementary to our chemical analyses, if we are determined to place ourselves in possession of the fullest possible evidence to be obtained from the samples of water submitted to us. But it must be recognised that bacteriological science is not the all-powerful thing that the unscientifically educated public is apt for the time being to suppose.Its difficulties have nowhere been better demonstrated than by Mr. Stoddart in this room, when he showed us how complex By R. F. Wood- Smith.THE ANALYST. 63 was even the single group of organisms usually associated together under the common designation of the Bacillus coli communis group. The separation and identification of the typhoid organism by the really beautiful methods demonstrated by Mr. Stoddart and its differentiation from its innocent cousins, is no doubt under some circumstances possible, but it appears to be very doubtful whether these circum- stances are the ordinary everyday circumstances under which the water analyst is called upon to act. What has occurred with reference to the terrible epidemic at Maidstone will act as a wholesome check to those who have cried out that bacteri- ology is everything, and that the bacteriologist is destined to supersede the chemical water analyst.I n Maidstone we have had one of the most severe epidemics of modern times, clearly traced, as far as circumstantial evidence can possibly go, to a particular portion of the public water-supply. Our past-President, Dr. Adams, as Medical Officer and Public Analyst for Maidstone, was charged with the duty of investigating this source of supply, and his analyses have given clear indications of undesirable contamination. But Dr. Adams has had associated with him in the inquiry one of our ablest bacteriologists, Dr. Washbourn, of Guy’s Hospital, who had before him what, from the bacteriologist’s point of view, must be regarded as a magnificent opportunity for demonstrating the value of bacteriology as a means of indicating specific infection.Dr. Washbourn, after a most exhaustive examination, has been unable to separate or identify the typhoid bacillus in the very water which, with more than mere presumption, may be said to have been distributing the disease-germs which he sought to find. Not only has Dr. Washbourn been unable to detect the typhoid bacillus, but he expresses his doubts as to whether in any of the earlier cases in which it is said to have been identified in connection with the dissemination of disease by water, the bacillus has really been discovered, its reputed discovery having been made when bacteriological methods were less precise than they are now, and when, 1 may add, it was easier to jump to rash conclusions.I n fact, although the typhoid bacillus may now be capable of satisfactory identification when once we can grow a colony of it, the difficulty of growing, or rather of lighting upon a colony, among the overwhelming progeny of concomitant organisms of the Coli cornmzmis group is so remote as to be, 8s Dr. Washbourn seeiiis to recognise, almost outside the field of practical labora- tory work. But Dr. Washbourn’s bacteriological examination must not, however, on this account be said to have been a failure. He has shown that in many cases the bacteriological condition of the water, while it has not sufficed to demonstrate specific infection, has sufficed to demonstrate faecal pollution in certain sources of the water- supply, thus giving independent confirmation of the chemical results of Dr. Adams.I will not say more about Maidstone, because I have asked Dr. Adams to come here and tell us, from the analytical point of view, the story of his work in connection with the epidemic, and I hope that at an early meeting he may be able to do so. But before leaving the subject, I would again say that, although I look forward with very little confidence to bacteriology as a practical means of identifying the typhoid bacillus under the ordinary circumstances of the spread of the disease by polluted water, I must repeat that I have the greatest possible faith in the value of bacteriology What has been the result?64 THE ANALYST.as an adjunct to the chemical analysis of water. For some years now I have made bacteriological cultures in every water sent to me for analysis, ascertaining the number of colonies per volume capable of growth on gelatin at the ordinary tem- perature, the number of colonies growable on agar at blood heat, and the number growable on acidified phenolized agar at the same temperature. Any analyst who will systematically do this side by side with his chemical analysis, and steadily compare the results, will after a time feel himself very greatly strengthened in pro- nouncing his opinion on the great majority of cases that come before him. Occa- sionally anomalous cases occur, and it is obvious that the origin of a water greatly affects the opinion to be arrived a t ; but the same thing is true of many of the chemical features of a water analysis.I think that any water analyst who has once systematically habituated himself to make such a bacteriological examination as that indicated would feel his judgment sadly lamed if he had for any reason to give up the practice, and to fall back upon his chemical results alone. I think, however, that the idea that the practice of such elementary bacteriology as is needed for practical purposes in the analysis of water requires for its understanding or accomplishment medical training or medical experience, or that the medical bacteriologist can find out something about a water which is beyond the powers of the ordinary public analyst who has learned simple bacteriological manipulation, has received its death- blow at Maidstone.Bacteriological examination of drinking-water is destined to become as everyday an operation as the determination of chlorides; but it is an operation that we can perfectly well undertake ourselves, and if we would recognise this, and learn to do it, our County Councils and local authorities will not think it necessary to hand over such work, which should properly be ours, to our medical brethren. The other paper that I mould single out for reference is that of Professor V. Storch, communicated to us last summer by our member, Mr. Harald Faber. I refer to this paper because it claims-and I do not think the claim, although disputed, has been set aside-to settle the long-debated question as to whether the fat-globules in milk are or are not surrounded by a special pellicle.Professor Storch, after a great deal of work, concludes that the pellicle after all exists, and, further- more, that it consists of a special and hitherto unrecognised proteid body. Among what may be called the doniestic incidents in our Society, we have had to chronicle during the year a very pleasant country meeting, held at Derby, under the hospitable auspices of Mr. Archbutt and Mr. White, when we had the pleasure of visiting the Midland Railway Works, the Crown Derby Porcelain Works, and the very interesting printing and lithographic works of Messrs. Bemrose and Sons, My predecessor, speaking from this chair a year ago, concluded his address with a devout hope that the Government would during the year introduce into Parliament a Bill based on the report of the Select Committee of the House of Commons on Food Products Adulteration, and that that Bill might not be crowded out by the plethora of less important matters.A part of that hope-viz., the introduction into Parliament of a Bill-was realized. You know already, however, that no Bill was introduced till the very end of the session, and then only as a mere formality ; and you know also how fragmentary and incomplete was the Bill which the PresidentTHE ANALYST. 65 and Secretary of the Local Government Board then produced. This Bill has been the subject of very anxious and careful deliberation on the part of your Council, and as a result of that deliberation a report has been issued, fully pointing out the directions in which the Bill should be amended in order to give substantial effect to the recommendations of the Select Committee.This report has been placed before the Local Government Board, and is being issued to all public authorities interested in the carrying out of the Food Acts, as well as to all members of Parliament. As B copy of the report has been placed in the hands of every member of the Society, and as it has been fully published in the ANALYST, and as, furthermore, the subject was discussed at some length by Mr. Kearley, M.P., at our recent annual dinner, I need not take up your time now by discussing it further. Suffice it to say that we were all severely disappointed by the Government Bill ; and that we hope that after all it may not have been the final intention of the Government to stop short at the very insufficient alterations in the law therein proposed, but that we may in the coming session be gladdened by the production of a fresh Bill, which shall, as I have said, substantially give effect to the recommendations of the Select Committee of the House of Commons, more especially with regard to the appointment of that Standing Committee of Reference, which is indispensable for dealing with the many vexed questions calling for settlement which cannot themselves be dealt with in a single Act of Parliament, however comprehensive.I n concluding these somewhat desultory observations, I have, as your President, to acknowledge the heavy and untiring work performed by our oEcers-the honorary secretaries and the horiorary treasurer.The year has been, owing to the important matters which we have had to consider, ZL toilsome one for our secretaries, and I am afraid that 1 cannot promise them much rest in the year that is to come; but I am sure their hearts are so fully in the rnultifarious work we shall have to get through, that the harder it becomes the more satisfied they will be. Mr. JOHN HUGHES, in proposing a vote of thanks to the President for his address, desired to make one remark on the subject of the exteiision of the Society. The President thought, and rightly, that they should look to an increased number of members as a means of increased revenue; and, while agreeing in this, he would venture to suggest that as the journal became more valuable, its price should be increased to those outside of the Society.He thought that if it were made more expensive to obtain the journal without joining the Society, the result would be an increase in membership. As it was, many persons obtained the advantages of the journal without being members of the Society. With regard to what the President had said with reference to the Institute of Chemistry in his address, he ( A h . Hughes) was not inclined to agree with the resolution which had been passed by the Institute Council, but he had not been able to be present at the last Council meeting. He did not see why the Institute should be called upon to furnish authority as to qualification in therapeutics ; he thought that what the Institute had to do was to give qualification in chemistry, and he did not see how it could give to chemists a qualification which many of its members themselves did not possess, or who the examiners were to be.He would have much preferred that the action should have been left to some other society-at all events, for the present; but he had no doubt that the Council of the66 THE ANALYST. Institute had gone into the question very much more fully than he himself had been able to do, and that they had been enabled to come to a right conclusion. Their own President had himself held at first somewhat different views on the question, and other members also had altered their views upon considering and inquiring into the matter, and he had no doubt that there were very good reasons for the passing of the resolution.Referring again t o the accounts, he certainly thought that the SUMS derived from life membership subscriptions should be funded in future, because they represented compositions of possible future payments. The motion was seconded by Mr. PERCY A. E. RICHARDS, and carried unanimously. The PRESIDENT said that he was pleased that Mr. Hughes thought that possibly, after all, the Council of the Institute of Chemistry had come to a, correct conclusion in the matter of therapeutical qualification. He certainly thought that the best thing was that all necessary examinations should be held by the Institute of Chemistry, and there would surely be no difficulty in finding proper examiners in the new subject. That, however, was not a meeting of the Institute of Chemistry, but of the Society of Public Analysts ; but the matter was so important a one, as affecting the particular branch of the profession in which so many members of the Society were engaged, that he had thought it right to take that opportunity of drawing attention to it.He now had to propose a vote of thanks to the President and Council of the Chemical Society for allowing the Society for another year to have the use of their rooms. If tliere were not some other society who would open its doors in this manner to them, the Society of Public Analysts would not be in such a good financial position as ih then was, for it would be taxed with heavy expenses for rental. He therefore had pleasure in moving from the chair that the cordial thanks of the Society of Public Analysts should be given to the President and Council of the Chsmical Society for the use of their rooms during the past year. The motion was carried unanimously. The following papers were then read : ‘( Copper ‘ pure for analysis.’ ” “Note on the tests for distinguishing boiled from unboiled inilk.’, Leffmann, M.D. The following is a list of the officers and Council elected for 1898 : President.-Bernard Dyer, D. Sc. Vice-Presidents (who have filled the office of President).-M. A. Adams, F. R. C. S. ; A. H. Allen ; Sir Chas. A. Cameron, M.D., F.R.C.S. ; A. DuprB, Ph.D., F.R.S. ; Otto Hehner ; Alfred Hill, M.D., F.B.S.E. ; J. Muter, M.A., Ph.D., F.R.S.E. ; Thos. Stevenson, M.D., F.R.C.P. Vice-Presidents (who have not filled the office of President).-A. P. Aitken, D.Sc., F.R.S.E. ; W. W. Fisher, M.A. ; J. A. R. Newlands. Hon. Treaszwer.--E. W. Voelcker, A.R. S.M. Hon. Secretaries.-E. J. Bevan ; Charles E. Cassal. Other Nenzbers of Council.-Bertram Blount, A. Wynter Blyth, M.R.C.S., R. Bodmer, A. C. Chapman, Sidney Harvey, C. G. Moor, M.A., S. Rideal, D.Sc., J. E. Stead, F. Wallis Stoddart, Walter J. Sykes, M.D., J. A. Voelcker, M.A., B.Sc., PbD., John White, W. C. Young. By J. W. Westmoreland. By H,
ISSN:0003-2654
DOI:10.1039/AN8982300058
出版商:RSC
年代:1898
数据来源: RSC
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The annual dinner of the Society of Public Analysts |
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Analyst,
Volume 23,
Issue March,
1898,
Page 67-74
Preview
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PDF (797KB)
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摘要:
THE ANALYST. 67 THE ANNUAL DINNER OF THE SOCIETY OF PUBLIC ANALYSTS. THIS was held on Tuesday evening, January 18, at the Criterion, under the chairman- ship of the President, Dr. Bernard Dyer. About sixty-five members and guests were present, amongst the latter being Mr. Hudson E. Kearley, M.P., Dr. Thos. Stevenson (President of the Institute of Chemistry), Professor Frank Clowes, D.Sc. (President of the Society of Chemical Industry), Dr. Seaton (President of the Society of Medical Officers of Health), Mr. Walter Hills (President of the Pharmaceutical Society), Professor W. A. Tilden, D.Sc., F.R.S., Professor Armstrong, F.R.S., Mr. C. E. Groves, F.R.S., Professor Dunstan, F.R.S., Dr. Pakes, Dr. Messel, Mr. Fred. W. Beck, Mr. Aubrey W. Rake, Mr. G. C. Barnes, Mr. H. Owen, and Mr.J. F. Owen. The Chairman of the London County Council (Dr. W. J. Collins), who was to have proposed the toast of “ The Society,” was prevented from being present owing to the funeral of his colleague, Mr. Ashley Ponsonby. The toast of ‘‘ The Queen ” having been duly honoured, The CHAIRMAN proposed ‘‘ The Houses of Parliament.” He said that when’ he had the honour, a year ago, of proposing the same toast, he was buoyed up with the hope, as most of them were, that before his year of office had expired Her Majesty’s Government would have produced a Bill which would have enabled Parliament to earn their thanks and congratulations for having placed upon the Statute Book an Act substantially giving effect to the recommendations of the Select Comm-ittee of the House of Cominons on Food Products Adulteration.That hope, as far as the past year at all events was concerned, was doomed to disappointment. The first shock was received when, at the opening of Parliament, they read the report of the Queen’s Speech, and saw with sorrow that there was no mention in that Speech of new food legislation. Their good friend Mr. Kearley (applause) made a gallant attempt to stimulate the Government into action by himself producing a very excellent Bill (hear, hear), a Bill which might very well, with perhaps a few altera- tions, have been adopted by Her Majesty’s Government with a considerable saving of time and trouble to that Departmmt, which Mr. Chaplin had lately told his constituents was so sadly overworked. While Mr. Kearley’s stimulant was not altogether without effect, it had, however, to act on a constitution that was not very acutely responsive to stimulants, and its action was feeble.It resulted in the pro- duction, by the President of the Local Government Board, at the end of the session, of a short Bill which was exceedingly disappointing (hear, hear). The saddest feature, perhaps, about that Bill was the signature on the back of it of Mr. T. W. Russell, the Parliamentary Secretary of the Local Government Board, who had sat as Chairman of the Food Products Adulteration Committee, and who with his own hand had drafted most of the recommendations of which the very Bill of which he was obliged to stand sponsor took no notice. There was only one ray of hope in connection with the whole matter, and that was the statement made by Mr.Chaplin when he withdrew the Bill simultaneously with its introduction, a statement that he invited expressions of public opinion on the matter. I t was to be hoped that even by that time public opinion had been expressed suEciently strongly to assure theTHE ANALYST. President of the Local Government Board that the small measure which he intro- duced satisfied not a single one of the many interests affected by food legislation. The Bill, such as it was, had been so recently dissected and discussed by the Council of the Society of Public Analysts, whose report had been circulated among the members of the Society, that he did not propose then to refer to any of its details. The report of the Select Committee was throughout pitched in a, very strong and very clear key, and its dominant note all through was the necessity for the appointment of a Standing Departmental Committee, or Court of Reference, which should deal with matters which could not possibly be dealt with completely in one comprehensive Act of Parliament.Public Analysts, as executive oficers under the Sale of Food and Drugs Act, knew perhaps better than most' people how urgent was the necessity for the formation of such a committee, if new legislation was to have any real effect for good on the food-supply of the country. The question, although a Parliamentary one, was not in any sense a party question. They were on the eve of a new session, and were hoping that Mr. Chaplin might introduce a Bill which should at any rate be some improvement on the one which he introduced a few months ago, and they hoped and trusted, and knew, that when that Bill was introduced their friend Mr.Kearley and those who thought with him in the House of Commons, no matter whether they sat on the one side of the House or on the other, would bind themselves firmly together to meet the necessities of the case, and to see that that Bill, if it required amendment, should be satisfactorily amended ; and they hoped that the efforts of those friends would finally result in securing a, satisfactory Act, which for many years to come should put an end to the many points on which so much burning discussian had arisen within the last few years. Mr. Kearley not only represented an important constituency of the British public, but he also, in his own person, represented the great mercantile interests of this country, and he was able to deal with this matter with a knowledge which was denied to many of those who sat with him in the House of Commons.Mr. Kearley had thrown himself for many years past with very great energy into this question, and they as Public Analysts, who wanted to do their duty better than they were able to do it at present, were grateful to him for the help that he had given to them in the past, and would give to them in the future; and he (the Chairman) would ask them, in drinking to the Houses of Parliament, to drink with that toast especially the health of their good friend and honorary member of the Society, Mr. Kearley (applause).Mr. HUDSON E. KEABLEY, M.P., said that he felt it an honour to have his name associated with that toast. The Chairman, in introducing it, had struck a note which appealed to him at once, in saying that at all events there was one question which had no party bearing, and that was the great question in which Public Analysts were so much interested. He was glad to be able to subscribe to that, and to go further and say that, in connection with the life of a member of Ynrliament, there was plenty of work to be done outside the limits of pure party obligations (hear, hear); and if there were pleasures that fell to the lot of members of Parliament, he would say that the most cherished were those that came from taking part in work that at all events contributed something towards the public advantage and welfare, and was not limited and confined as party work pure and simple naturally was.HeTHE ANALYST. 69 was sure that the company on that occasion were more interested in this particular question of food-products adulteration than in any other question, and therefore he would trespass on their attention by making some observations as to the course which legislation attempted to take during the last session, and as to the prospects that it might have during the forthcoming one. The Chairman had referred to the con- siderable disappointment experienced on all hands by the inadequacx of the legisla- tion proposed in Mr. Chaplin’s Bill. That Bill was a remarkable one, in so far as it was introduced at the expiry of the session merely in fulfilment of a pledge that a Bill should be introduced. No one vithin the walls of Parliament thought for a single moment that the Bill was intended seriously.Mr. Chaplin himself, indeed, rather described it as a ballon en Z’air, and evidently expected that during the Parliamentary recess his abortive Bill would be torn to pieces, with the object of inducing him to introduce a more satisfactory measure. There would be plenty of criticism as to the direction which Mr. Chaplin should take in the coming session in bringing about a more perfect measure. The Bill introduced at the close of the last session simply, in his (Mr. Kearley’s) opinion, trifled with a great national question. All the way along ihere had been ample evidence of technical and scientific difficulties which rendered it impossible for the present statutes to be effectual.A magistrate in a case was, perhaps, called upon to decide a technical question-it might be as to the percentage of borax that should be permitted in butter. One of their friends might come and declare that 0.5 was a, perfectly safe percentage of borax to be introduced, while some more energetic gentleman might declare that 0.7 per cent. was a safe quantity, while the trembling criminal in the dock did not know what a borate was, and the gentleman on the bench probably did not know either, yet he gave a verdict, and fined the man forty shillings. All this had been impressed upon the Select Committee in the valuable evidence that they had been permitted to hear during three sessions, and the conviction grew in their minds that, as such questions were of a scientific and technical nature, it necessarily followed that they must have a scientific Board of Reference to whom these questions should be referred (hear, hear).The Select Committee differed very much among themselves upon certain other details : some of their agricultural friends, for instance, were, figuratively speaking, for hanging all margarine manufacturers, or preventing them from coloring their productions ; but they all agreed with perfect unanimity that to deal with these scientific ques- tions it was absolutely necessary that there should be constituted this Board or Court of Reference (hear, hear). But Mr. Chaplin in his Bill altogether ignored this strong and unanimous recommendation of the Select Committee, which was sup- ported by the opinion of all the public bodies that came before them, The Corpora- tions of Glasgow and other important towns sent competent gentlemen to give evidence, who supported the requirement of this Court of Reference.The merchants who came before them also supported it, and the retailer for his own protectioii demanded it. Even the agriculturists agreed, while analysts of course assented ; and, above all, the Government oficials themselves agreed. It was, however, ignored altogether, and he oould not satisfy his mind as to the cause of its being so ignored, unless it arose from the fact that the Government had altogether a misconception of70 THE ANALYST. the grounds of this great question.He rather imagined that they thought that the pressure which was being brought to bear upon them in Parliament was instigated by the agriculturists in the House of Commons, and he expected that each party was rather suspicious of its agricultural adherents. The agriculturists had certainly made some extreme proposals, and he could not help thinking that the Government might have thought it was the agriculturists who were pushing the movement forward. He said that advisedly, because Mr. Balfour, replying to a question which he {Mr. Kearley) had recently put to him in the House of Commons, had said that it was a very controversial question, and one which raised serious differences between town and country; and he rather imagined that that gentleman also shared the belief that the country people were trying to run a racket ” of their own to the detriment of the towns.Now he (Mr. Kearley) spoke as a townsman, and his views arose from his knowledge of the iniquity of the adulteration that went on unchecked in every town. It was not merely in towns, but in the poorest parts of towns, that adulteration was carried on to the greatest extent. London at that very moment was overwhelmingly full of adulteration, and it was the poor of the Metropolis and the other great centres of England who were the greatest sufferers. He desired himself, if he could, to dissipate the idea that this was a purely agricultural question. It was one which affected the towns more vitally than it did the agricultural districts of the country, So bad had adulteration now become, and so ineffectual had been the operations of local bodies to check it, that it had become necessary for those who were deeply interested in the subject to establish, as it were, their own police.There was in London what was known as the Butter Association, who were running to earth week by week some of these fraudulent gangs. In Lancashire the Agricul- tural Association had appointed its own inspectors, and was doing good work. According to their report they had taken last year 277 samples, of which no less a number than 135 were adulterated. That was a very serious amount of evidence as to the adulteration that existed. He was sure, froin very intimate knowledge of the effects of such unchecked adulteration, that its continuance would ultimately sap the commercial honesty of the country.I t was becoming a species of competition. Mr. John Bright, some forty years ago, had described adulteration as a form of competition, which might have been perfectly true in those days; but he (Mr. Kearley) would describe it as a form of robbery, and of the nioslj gross and flagrant character (hear, hear); and the man who was subjected to such competition-if it were called competition, was perfectly entitled to claim the protection of the law. A man who put 30 per cent. of water into milk was a far greater criminal than any poor and starvipg man who committed a petty theft, although the latter would no doubt receive the heavier punishment. Those who practised adulteration battened and fattened on it, simply because the penalties that were inflicted upon them were quite inadequate to the amount of crime they committed (applause). He would not go further into the details of the abortive Bill that had been introduced by Mr.Chaplin, but he did feel it a pleasure to have the opportunity of supporting before Parliament the cause advocated by the Society of Public Analysts, He had had the honour on two occasions to move an amendment to the Address at the opening of Parliament, and he would look forward to the Queen’s Speech with just the sameTHE ANALYST. 71 amount of interest on this occasion as he had done in preceding years. He hoped that there would be found a direct reference in that Speech to the determination of the Government to introduce a Bill, and if there was not, he should feel it his duty to again move an amendment to the Address, and it would be his endeavour and intention, all through the session upon which they were about to enter, to induce the Government, in the interests of Public Analysts, in the interests of consumers, and in the interests of distributors, to bring in a Bill that would be satisfactory to all those who were concerned, and he hoped that if he had the honour to be with the Society again next year, he would be in a position to congratulate thein on the success of their endeavours (applause).Professor TILDEN said that he had accepted with great pleasure the invitation to propose the toast of ‘‘ The Institute of Chemistry,’’ because, as he thought was well known, he had been very much interested in watching the progress of the Institute during many years.The Institute of Chemistry was established at a time when there did not exist in England any Society or Institute which was prepared to test the qualifications of chemists, and he used this term “ chemist ” advisedly, notwith- standing that he had had the advantage of sitting during the evening next to his friend, the President of the Pharmaceutical Society. It was well known, of course, that the Pharmaceutical Society, always forward in the field, had some forty years ago got a Parliamentary stamp put upon the type of chemists which it represented, and claimed patent rights in respect of this title. However, he thought he might venture to claim that he was on very good terms with his friend, whom, he had no doubt, the company would find desirous of being on good terms with them.The Chemical Society, which of course was an old Society, having long ago celebrated its jubilee, was approached more than twenty years ago on this question, and it was asked whether a department of the Society could be established, the object of which should be to inquire into the professional qualifications of young chemists, and t o put upon thein a kind of stamp which would be intelligible to the public. The Chemical Society did not at that time see its way to doing anything of this kind, and so, in 1877, the Institute of Chemistry was established. It went on for a few years, until in 1855 it received a Royal Charter, which for some time, as far as he could remember, did not seem to quite agree with it.A few years later it fell to his lot to offer certain advice, which he thought did it some good, although occasionally the advice that he ventured to offer had been received with rather a wry face. E e said that not because he wanted to claim any credit in the matter, but because he wanted to suggest to the Institute that it must take another step or two in order to reach that position which all its fellows and all its well-wishers desired it to occupy. There had been a great deal of talk about its occupying, in regard to the profession of chemistry, a position corresponding to that which was occupied by the College of Physicians towards the proie3sion of medicine, and various other parallels and comparisons had been drawn with it. The Institution of Civil Engineers had been quoted as an instance of the sort of body which it ought to imitate.E e ventured to say that the Institute of Chemistry was successfully imitating this greater and older Institution in every respect but one. I t was carrying on its work in a thoroughly e&cient and satis- factory manner, It was doing that which he considered to be the main object of its72 THE ANALYST. existence, namely, testing the professional qualifications of the younger chemists by zu proper system of examination following upon a course of systematic study, and putting upon them a certain stamp; and it gave them a kind of position in the professional world. He did not know that the College of Physicians or the Institu- tion of Civil Engineers did any more than this ; but the difference was that the older bodies had comniand of very considerable monetary resources.He believed that the Institute of Chemistry only required to be in a stronger financial position to become one of the most influential bodies which existed in the Metropolis, or in this country, and, though he really did not know how it was to be done, he suggested to the President and Council, now that they had set their house in order, and had a roof of their own over their heads, and were carrying on work that was of eminent practical value and eminently serviceable to the community, that they ought to proceed somehow or other to get money. Then, he thought, the Institute would be in a really important position, and capable of exercising that kind of influence upon public opinion which at present it was not in a position to exercise.This was the advice that he now ventured to offer to the Institute ; how it was to be carried out he left it to the President and Council to take into early consideration. He would not like to conclude without coupling with this toast the name of the present President of the Institute of Chemistry. The present President lived in happy times. The Institute was no longer divided by those sharp contentions, no longer disturbed by those fierce discussions which took place a few years ago, when he (Professor Tilden) was on the Council. The present President had a united Council to work with, and a definite and fixed organization of the Institute and its work to preside over, and he might say that Dr.Stevenson had shown that he possessed the qualities of the best President that the Institute could have. H e certainly was a man repre- senting the sort of professional position that the Institute desired ; he was a man of peace, and at thesame time a man of action, and he (Professor Tilden) was sure Ghat under Dr. Stevenson’s guidance the Institute would go on and prosper more and more year after year, DR. STEVENSON in returning thanks, in the name of the Institute of Chemistry, for the kindness with which this toast had been proposed and received, said that Professor Tilden had omitted one very important fact, namely, that he (Professor Tilden) was himself one of the former Presidents of the Institute who fought those battles of which he had given such a graphic description.He (Dr. Stevenson) felt that as President of the Institute of Chemistry he had indeed fallen upon very happy times. €Ie was present in somewhat of a double character, for he was present as one of the oldest members, and as a former President, of this Society, aEi well as in the capacity of President of the Institute of Chemistry; and he felt it a great compliment that as soon as he ceased to be President of the Society of Public Analysts he became the President of the Institute of Chemistry. The times, he hoped, were past when there was any feeling of uncordiality between that Society and the one which he officially represented. He ventured to think that the Institute was conferring a great benefit upon the Society of Public Analysts.I t had already instituted examinations which, for completeness in testing professional and chemical knowledge, surpassed those of any other society. I t s membership was now without question accepted by the LocalTHE ANALYST. 73 Government Board as a complete qualification in everything required of a public analyst except therapeutics, and with regard to therapeutical knowledge he hoped that the gap would soon be bridged over, and that the Institute would formulate a complete qualification for Public Analysts, as far as the Local Government Board was concerned. Mr. BERTRAM BLOUNT, in proposing the toast of ‘( Kindred Societies,” said that among the societies coming under this head the Chemical Society might properly claim the first place. Analysts, unless they received an education in the science of chemistry as distinct from its profession, would have a remarkably poor chance of success, and if they were unable to produce evidence of a knowledge of the science as such, they would not be proper representatives of a great and growing and most honourable profession.He was therefore sorry to have to refer to the absence of the President of the Chemical Society, Professor Dewar, consequent upon lecture engagements in Cambridge ; though they welcomed three most eminent members of the Chemical Society, namely, Professor Armstrong, Professor Dunstan, and Mr. Groves. He coupled the toast with the name of the President of the Society of Chemical Industry, Professor Clowes. Professor CLOWES, in responding, said that in addition to the society which he had the honour to represent, he had to speak on behalf of several other societies, and he had been greatlyassisted by the kindness of Mr.Blount in enumerating them. He considered it remarkable that in spite of the increased number of societies, their membership showed no signs of decreasing. He was not aware that the Chemical Society had suffered in any way from the existence of the Society of Chemical Industry, and he was quite sure that the latter society had not suffered in any way from the existence of other societies, the fact being that its membership was increasing faster than ever. Every one of these societies was really required, and each had been con- stituted to meet an acknowledged need. He returned hearty thanks for the toast on behalf of all the societies that had been referred to, and expressed the hope that they would all continue to work in a friendly way with the Society of Public Analysts.Mr. WALTER HILLS (President of the Pharmaceutical Society), in proposing the toast of “The Society of Public Analysts,” said that probably most of those present were members of the Society of Public Analysts, and would naturally feel a great interest in its prosperity, and he was sure that that prosperity would continue to increase as long as the Society’s object continued to be the benefit of the public. His opinion was that no society could flourish unless it .existed primarily for the advantage of the public, and he believed that the Society of Public Analysts was doing good work in the interests of the public.I t therefore gave him very great pleasure to propose prosperity to it, Mr. Kearley had referred to the Bill which had been recently introduced in the House of Commons by Mr. Chaplin. He (Mr. Hills) had great sympathy with all that Mr. Kearley had said, and would only say in addition, with regard to the calling which he had the honour to represent, that he was sure it would be agreed that, in the Board of Reference which had been recommended by the Select Committee, there should be someone who was representative of the great pharmaceutical interest, for the examination of drugs was attended by more difficulties, perhaps, than the examination of ordinaryTHE ANALYST. articles of food. The subject of milk had often been discussed rather as typical of those matters which came constantly under the purview of the Public Analyst ; but the difficulties arising in connection with milk were intensified in the case of drugs.The subject of milk, moreover, was free from the special difficulties arising from the use of synonyms, which were a great bugbear in connection with drugs. Another difficulty was that many drugs were collected by totally unqualified persons, who did not know the right time to collect these various vegetable products, and who sent to this country products possessing widely different pharmaceutical and thera- peutical values. With regard to the Society of Public Analysts itself, it had been in existence for some four-and-twenty years, and had been constantly progressing. It was formed for the protection of the public, it had the interests of the public at heart, amd it was trying to furnish for the service of the public a number of persons possessing certain special qualifications. I t was, moreover, the proprietor of the ANALYST, which was a most valuable periodical. With the proposition of prosperity to the Society of Public Analysts, he had the pleasure of coupling the name of the Society’s President. The PRESIDENT, in acknowledging the toast on behalf of the Society, referred to the self-sacrificing and indefatigable labour of Dr. Sykes in editing the ANALYST, with results which he thought were satisfactory to every reader of that journal, and the readers of the ANALYST were not merely the members of the Society. The paper went abroad all over the world, and was taking up a very strong position wherever the English language was read, and wherever analytical chemistry formed a subject of interest. H e hoped that when the time came for him (the President) to finally resign his official connection with the Society, he would be able to con- gratulate it upon the fact that the great question of the amendment of the Sale of Food and Drugs Act, which had been exercising their attention for so many years, had been finally settled. Mr. CASSAL proposed the toast “ The Guests.” Professor ARMSTRONG, in replying, said that the Society was doing a work on behalf of the public which was of extreme importance. I t was not necessary for hiin to say more than this in returning the guests’ most hearty thanks for the toast. The health of the Honorary Treasurer, Mr. E. W. Voelcker, and of the Honorary Secretaries, Mr. Edward Eevan and Mr. Charles E. Cassal, having been proposed and acknowledged, :he proceedings terminated.
ISSN:0003-2654
DOI:10.1039/AN8982300067
出版商:RSC
年代:1898
数据来源: RSC
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4. |
Foods and drugs analysis |
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Analyst,
Volume 23,
Issue March,
1898,
Page 75-77
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PDF (175KB)
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摘要:
THE ANALYST. 46-24 37-79 47.89 11.10 75 2.24 3.11 1.12 0.09 - 135 - 2.17 ABSTRACTS OF PAPERS PUBLISHED IN QTHER JQURNALS. FOODS AND DRUGS ANALYSIS. (Zeit. maZ. Chem., 1897, xxxvi., 751-766.)-The author recommends the following as a simple method of obtaining the fat without material alteration and without free fatty acids or lactic acid. From 50 to 100 grammes of the cheese cut in small pieces (or triturated with a little water in a mortar) are .mixed with 50 to 80 C.C. of water, and 100 to 150 C.C. of ether in a Wolfbauer shaking flask (a stoppered flask with a small constriction in the middle), Two or three drops of phenolphthalein solution are added, and the whole well shaken with dilute potash until the aqueous layer becomes perceptibly pink. The ethereal layer is then drawn off, the ether distilled, and the fat dried at 100" C., filtered if necessary, and examined in the usual way.A table giving the constants of the fat thus obtained from fiEty-one kinds of cheese (including margarine cheese) is given in the paper. For the determination of the water about 10 grammes of the finely-divided cheese are dried in vacuo over sulphuric acid at the ordinary temperature for 24 to 36 hours, and then for 2 to G hours at 100" C., until the weight becomes constant. I n this way the bulk of the water is removed at the ordinary temperature, and whilst the method is as speedy, there is no material loss of organic matter (volatile glycerides and acids) such as occurs with long-continued drying at 100" C. Complete drying in vacuo is too tedious, and often impracticable.The following examples show the accuracy of this process : The Determination of Fat and Water in Cheese. A. Devarda. Cheese. ~ Rodamur . . . Limburg ... Gervais ,.- Limburg (air-dried) . . Loss of Water per cent. Water per cent. 51.59 39.00 49.25 13.27 Per cent. Water. Dried entirely a t 100" C. 51.92 39.38 49.36 13-46 Dried entirely in vacuo. 51.50 38.98 49.10 C. A. M. The Composition of some Commercial Powdered Extrttc ts of Liquorice. c. 0. Kinzey. (Amer. Jour?z. Pharnz., 1898, lxx., 23-25.)-The method most in use for the determination of glycyrrhizin, on the amount of which the value of extract of liquorice extract depends, consists in exhausting the extract either with boiling water, cold water made alkaline with ammonia, or with a cold mixture of water and alcohol made alkaline with ammonia, and precipitating the glycyrrhizin in the filtrate with dilute sulphuric acid.But the author, finding the direction., given by76 THE ANALYST. other chemists vague, and often experiencing considerable difficulty in filtering the insoluble residue, made experiments, and found that the most satisfactory results could be obtained by using as a solvent a mixture consisting of official alcohol 240 c.c., official ammonia water 40 C.C. (Amer. Phurmucopsia), and water to make up a litre. One gramme of the extract was treated with 25 C.C. of the solvent, stirred at intervals for an hour, and left, for twelve hours. The supernatant liquid was decanted on to counterpoised filters, the residue washed with 5 C.C.of the solvent, then trans- ferred to the filters, washed till the washings were colorless, and dried in the air-bath at 100" t o 110" C. The filtrate was acidified with dilute sulphuric acid, and the precipitate of glycyrrhizin collected on counterpoised filters, washed until free from sulphuric acid with water containing a litt'le acetic acid, dried in the air-bath at 105" C., and weighed. The following table gives the percentage results obtained with samples of different commercial brands : Brand. Spanish Greek Spanish American Spanish Spanish Greek - __ - - __- Moisture. 6.52 6.26 5.00 5.62 7.08 6.96 6.71 7.96 8.25 8-16 9.19 5.78 (Cf. ANALYST, xxii., 192, 219.) Ash. 3-70 8.18 5.51 6.79 6.52 6.56 7.82 5.77 5.54 4.67 6-76 7-49 Insoluble Matter. 36.52 22-06 25.54 12.27 29 -20 20.35 9.65 15.21 7.40 19.41 11-12 5-95 Glycyrrhizin.6.40 14.39 10.75 7.63 5.28 10.41 18.59 8.90 27.78 9.50 8.94 11.63 C. A. M. A Reaction for Chloroform, Bromoform, and Chloral. A. Desgrez. (h. d. Sc., 1897, 780 ; through JOW. Phum. Clzim., 1898, vii. , 35, 36.)-Chloroform is decomposed by aqueous potash, giving as the principal products carbon monoxide and water in accordance with the equations :- CHC1, + 2KOH = 2KC1+ H,O + CO + HC1 and CHC1, + KOH = KCl + 2HC1+ CO. The carbon monoxide may be recognised by its blue flame, by its absorption in a solution of cuprous chloride in hydrochloric acid, by Berthelot's test (ammoniacal silver nitrate), and by the result of combustion with oxygen in the eudiometer. The reaction is accelerated by a gentle heat, and by the presence of light. Bromoform is decomposed in ~l similar manner, though more slowly, but iodoform, being insoluble in water, is not affected, as is also the case with carbon tetrachloride and methylcne chloride, Chloral gives the same reaction as chloroform, but moreTHE ANALYST. 77 rapidly on account of the heat generated by its primary decomposition into chloro- form and formate accelerating the action of the potash. Alkaline carbonates and bicarbonates do not cause an analogous decomposition, and ammonia is also without action in the cold. C. A. M.
ISSN:0003-2654
DOI:10.1039/AN8982300075
出版商:RSC
年代:1898
数据来源: RSC
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5. |
Organic analysis |
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Analyst,
Volume 23,
Issue March,
1898,
Page 77-80
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PDF (352KB)
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摘要:
THE ANALYST. 77 ORGANIC ANALYSIS. On Dsuro Olive Oil. A. J. F. Silva. (BulZ. Soc. Chew., 1898, xix., 88-89.)- Milliau was the first to point out that certain kinds of olive-oil contained a coloring matter derived from the aqueous part of the pulp of the fruit which gave a rose coloration with Baudouin's reagent. He also showed that by applying the test to the dried fatty acids instead of to the oil itself, the effect of this might be obviated. Domergue established the same fact in the case of olive-oil from Tunis a,nd Algiers, whilst Villavecchia and Fabris found that some varieties of Italian oil behaved in the same way. Similarly the author finds that the best varieties of Douro oil give a violet coloration with sugar and hydrochloric acid, but that their dried fatty acids give a negative result.The samples examined were perfectly normal in appear- ance and taste, and as regards their physical and chemical constants. As Toche's reagent gave no coloration with these oils, the author prefers it l o Baudouin's for the detection of sesame-oil in olive-oil. Fifteen gramiiies of the oil are shaken with an equal quantity of a solution of 2 grarnnies of pyrogallol in 30 graiiiines of hydrochloric acid, and after being left for some time, the oily layer is decanted, and the hydrochloric acid warmed for five minutes. The appearance of a reddish-purple colour denotes the presence of sesame-oil. C. A. M. Testing Oil Paints. H. Loesner. (Chenz. Rev. Fettu. :Im.z-Iml., iv. [24], 329-330.)-1n order to determine the permeability of a paint, and consequently gauge its value as a protective coating for iron, the author proposes to employ a steam test.A thin, uniform layer of the paint is applied to the surface of a polished strip of sheet- iron (2 by 4 inches), followed by a second coating when the first is dry. The strip, when dry, is then laid, with the painted side downwards, over the opening in a water-bath, and supported by strips of wood (to prevent mechanical injury) so that the surface of the paint is two inches above the constant level of the water. After exposure to the steam of the bath for fifteen hcurs, the strip is dried at a iiiaximunl temperature of 100" C., and after loosening and removing the paint with aniline, its surface is examined for rust. Resistance to acids may be tested by exposing the painted strips to the fuines of 33 per cent.hydrochloric acid at 20" C., the distance between the surface of the paiut and the level of the acid being the same as in thesteam test. The incrustation formed on the paint must be removed by washing at intervals, and at the end of twelve hours the paint is removed as before and the metal examined for corrosion, The steam test is also useful for examining fats, vaseline, lacquers, etc., intended78 THE ANALYST. for use as rust preventors. Any of these substances that will stand the test for four to five hours may be regarded as satisfactory, but for oil paints twelve hours is the minimum exposure permissible. c. s. Characteristics of some scarce Resins. K. Dieterich. (Chenz. Rev. Fett u. Hair.x-I7zd., vol.iv. [24], 327-329.) CyzLde Chicle Gum, obtained from Achq-as Sapota, is particularly rare. It contains 70 per cent. of resin, 10 per cent. of gum, 9 per cent. of calcium oxalate, 5 per cent. of sugar and inorganic salts. The pure resin can be extracted by carbon disulphide ; it forms a plastic mass, which resembles guttapercha, and can be vulcanized. GZLGL~CLCZL~L in lacryinis, another scarce resin, gives an acid number, 72.8-75.6, by the author’s method, whilst that of the ordinary guaiacum is 89.6-92-5. Xocotru Drayoiz’s Blood. The pure red resin from this variety is a mixture of several resins, and differs from Palm Dragon’s blood in lacking the draco-alban, characteristic of the latter. -4part from this and their varying solubilities, little difference exists between their other characteristics.Bimbo1 J f y w I i differs from the ordinary Herabol myrrh of commerce. To prevent errors-arising froin the examination of the alcoholic extract instead of the natural drug-the author proposes the following method of determining : One gramme of a very finely powdered average sample of the myrrh is heated along with 30 C.C. of water for a, quarter of an hour under a reflux condenser, and then for a similar period with 50 C.C. of strong alcohol. After cooling, the liquid is titrated with $ alcoholic potash, using phenolphthalein as indicator. 2. Snpom$cc~tio/~ wtdzie. One gramme of an average sample is infused in 30 C.C. of water, and after standing for half an hour, mixed with 33 C.C. of alcoholic potash, boiled for half an hour under a reflux condenser, then cooled, diluted with alcohol, and titrated back.1. The Acid Nzinzbw. 3. Ester ?z.zinzbet* by difference as usual. The following values were obtained for the two varieties : Acid Ester Saponification Solubility in Alcohol. Number. Number. Value. Bisabol Myrrh 20.06 125.54 145-6 50 per cent. Eerabol Myrrh 25.48 204.12 229% 20 per cent. c. s. The Preparation of Absolute Alcohol by means of Calcium Carbide. p. Yvon. (Jozw. Plum?z. Chim., 1898, vii., 100-102.)-Calcium carbide furnishes a ready means of determining whether alcohol is anhydrous or not. On adding a pinch of the powder to several C.C. of absolute alcohol, no bubbles of gas are liberated and the liquid remains transparent, whilst if only a trace of water is present, bubbles of acetylene are liberated, and the liquid becomes milky from the formation of calcium hydrate.I n order to prepare absolute alcohol from 95 or even 90 per cent. alcohol, the latter79 THE ANALYST. is mixed with about one-fourth of its weight of powdered calcium carbide, shaken a t intervals during two or three hours, and then left for twelve hours, when all libera- tion of acetylene should have ceased. It is then cautiously distilled, the first portion, which contains acetylene, being rejected. The alcohol obtained is usually anhydrous, but it is advisable to redistil after the addition of a little copper sulphate to remove acetylene. C. A. M. Reducing Action of Mineral Acids on Fehling's Solution. 3%. Z. Jovitschitsch. (Berichte, 1897, 2,43l.)-The author finds that the addition of small quantities of the mineral acids to Fehling's solution by lessening its alkalinity effects its reduction, even when the liquid is still alkaline to litmus paper, just as effectually as such reducing bodies as glucose, phenylhydrazin, etc. Often the action commences before the liquid is warmed, as in the following case : If to 1 or 2 C.C.of Fehling's solution a few drops of a dilute mineral acid are added in quantity insufficient to discharge the blue colour, and then a few drops in the original Fehling, a turbidity indicating reduction immediately appears, which may be completed by gently heating the liquid. Tartaric acid, employed in a similar manner, also causes reduction. The cause of this is supposed to be the decomposing action of the mineral acid on the tartaric acid of the Fehling's solution; and the reduction which occurs when this solution is kept for Some time in well-closed bottles is attributed to spontaneous decomposition of the tartaric acid.PI. J. S. The Chemical Examination of Saliva. E. Gerard. (Jozw. Plzarnz. Chim., 1898, vii., 12-15.)-This paper deals inore especially with a, pathological case in which an excess of saliva was secreted by an epileptic patient, but also contains remarks on the composition and analysis of normal saliva. The analytical results obtained by the author were : Density at 15" C., 1.003 ; total solids, 7.85 per cent. ; ash, 4-80 per cent. ; substances precipitable by alcohol, 2.30 ; mucin and albumin, traces. The proportion of salts here is higher than in normal saliva, and bears out Heidenhain's law that the more rapid the secretion, the greater the percentage of mineral matter.It has been shown by several chemists (e.g., U. Gautrand, Thlse de Lyofi, 1895) that the amylolytic power of saliva shows a considerable variation under the influence of different diseases. For this determination Jawein's method ( Wien. Mecl. Press, xxxiii., 626) was adopted. To 100 C.C. of a 4 per cent. solution of starch 4 C.C. of the saliva were added, and the mixture kept at 39" to 40" for fifteen minutes. It was then diluted to 200 c.c., and the percentage of maltose determined. This varied on different days from 0-603 to 0.639 gramme, whereas normal saliva yields from 0.368 to 0555 gramme. The temperature at which the ptyalin became inactive was determined on the ptyalin itself, obtained by precipitation with alcohol and dissolved in water, following the directions of E.Bourquelot (Ferments XoZzLbZes, 1896, 136). In the author's case the ptyalin was still active at 57" C. , became enfeebled at 58" to 59" C.,80 THE ANALYST. and inactive at 60" to 61" C. In this respect it behaved like the ptyalin of normal saliva. This saliva contained an oxidizing ferment, which has also been found in the normal secretion by P. Carnot (C. R. Xoc. Biol., May 29, 1896). C . A. M. The Influence of Certain Drugs on the Analysis of Urine. B. Bardach. (Zeit. anal. Chem., 1897, xxxvi., 776-784.)-I. The Influence of Nitrates o n the Determination of Nitrogen by Kjeldahl's Method.-In order to obviate the loss which occurs when the nitrogen in urine containing nitrates is determined either by Kjeldahl's original method, or by the Jodlbauer-Foster modification, or with the addition of phenol to the sulphuric acid, the author has devised the following process, in which the nitrates are first reduced in alkaline solution : Ten C.C.of the urine are placed in a 500 C.C. Kjeldahl flask, together with about 0.3 gramme of aluminium strips (previously heated), 20 C.C. of water and 5 C.C. of soda-lye (specific gravity 1.34) added, and the flask rapidly connected with an absorption flask con- taining a known quantity of standard sulphuric acid. The flask is left for about forty-five minutes, being occasionally shaken, and is then heated on a wire gauze over a, small flame for about five minutes, until the development of gas has prac- tically ceased.The flask is then cooled by drawing air through it, 30 C.C. of con- centrated sulphuric acid added (and subsequently some potassium permanganate), the liquid heated until colorless, and the ammonia distilled over in the usual way. The following are some of the results thus obtained, calculated on 100 C.C. of the urine : Nitrogen of the Added Nitrogen in Total Nitrogen Urine. the form of Nitre. Calculated. Found. Grammes. Gramme. Grammes. Grammes. 0.884 0.348 1.23 1-25 0.788 0.069 0.857 0.849 1.000 0.173 1.173 1.169 11. On the Determination of Urea by Liebig's Method.-Salkowski (Pflug. Arch. f. Phys., vi., 244) pointed out that potassium iodide had an influence on the deter- mination of urea, since, owing to the formation of mercuric silver iodide the end- point of the reaction occurs too soon, and the amount of urea found is too low. This error, however, is considerably modified by the addition of sodium chloride, and owing to the presence of that salt in normal urine is comparatively trifling. The author finds that amm-oniurn chloride has a similar disturbing influence, but in the opposite direction, delaying the end-point of the reaction, and causing the amount of urea to appear too high. This error is considerable with little more than 0.3 per cent. of ammonium chloride, and with largsr quantities the results are entirely worthless. 111. On the Determination of Uyic Acid.-Experiments are described which prove that the usual doses of lysidin and piperazine have no appreciable effect on the results of the determination of uric acid by Salkowski's method (Prak. d. phys. 26. path, Chew%., 239). Similarly in the case of potassium iodide the author obtained correct results, although great care was necessary to avoid loss. C. A. M.
ISSN:0003-2654
DOI:10.1039/AN8982300077
出版商:RSC
年代:1898
数据来源: RSC
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6. |
Inorganic analysis |
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Analyst,
Volume 23,
Issue March,
1898,
Page 81-84
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摘要:
THE ANALYST. ‘81 INORGANIC ANALYSIS. A. Hallard. (An%. de Chim. Analyt., ii. [13], 242.)-By digesting out of contact with the air pure precipitated copper sulphide for a sufficient time with concentrated sodium sulphide (specific gravity 1.225), prepared according to the directions given by Classen, and saturated with hydrogen sulphide, it was found, after filtering the liquid with due precautions to prevent oxidation and throwing down the dissolved copper by electrolysis, that the maximum amount of copper in the condition of sulphide that can be dissolved by 100 Solubility of Copper Sulphide in Sodium Sulphide. C.C. of sodium sulphide is 0.0032 gramme. c. s. The Separation of Thorium from Cerium. E. Hintz and H. Weber. ( Z e z t , anal. Chem., 1897, xxxvi., 676-685.)-After experimenting with different analytical methods, the authors have arrived at the conclusion that the separation of thorium from cerium by means of sodium thiosulphate is not absolute, a small amount of thorium remaining in the solution and of cerium in the precipitate, but the errom resulting from this are only trifling, and to a large extent compensate one another.The separation by means of ammonium oxalate is also incomplete in a single precipitation, and, although better results can be obtained by repeated precipitation, yet the amount of cerium formed is still slightly too high in spite of the fact that traces of cerium can be detected in the filtrate. Very small quantities of thorium oxalate, however, can be completely dissolved by one treatment. Glaser’s method (ANALYST; xxi., 274), based on the solubility of thorium oxalate in a solution of ammonium oxalate containing ammonium acetate, has, according to the authors’ experiments, the same drawback, and they recommend the thiosulphate method as being the most satisfactory for the analysis of incandescent mantles and thorium nitrate.The most accurate results are obtained by adding ammonia to the filtrate from the thiosulphate precipitation, dissolving the precipitate in acid, expelling the latter by evaporation, adding oxalic acid, and extracting the sinall amount of thorium oxalate with ammonium oxalate. C. A. M. On the Determination of Insoluble Phosphorus in Iron Ores. C. T. Mixer 2nd E. W. Dubois. (Jour. Amer. Chem. SOC., 1897, xix., 614-619.)-The following simple process is based on the fact that ignition of the residue insoluble in hydrochloric acid converts the insoluble phosphorus into a soluble form’: About 19 gramme of the ore is treated with 25 C.C.of hydrochloric acid (specific gravity 1-10), and when as much as possible has dissolved, the excess of acid is expelled by evaporation, and the liquid dilnted and filtered. The residue and filter paper are ignited in a platinum crucible at a red heat for a couple of minutes, the mass being stirred with a, platinum rod. It is then placed in a beaker with a little water and a few drops of hydrochloric or nitric acid, the liquid gently boiled for about five minutes, filtered into the flask containing the first filtrate (or into another flask if this portion is to be determined separately), neutralized with ammonia, and the phosphorus precipitated as ammonium phospho- molybdate and titrated.82 THE ANALYST.The results obtained in this way are in close agreement with those given by the older method of dissolving the ore and fusing the residue with sodium carbonate. The authors’ objections to the latter are, that a longer time and larger crucibles are required for the fusions, and that the introduction of a sodium salt is often unfavour- able to the obtaining of a pure precipitate of ammonium phosphomolybdate. C. A. M. Determination of Citrate-Soluble Phosphoric Acid in Thomas Phosphate Meal. 0. Bottcher. (Chem. Zeit., xxi., 993.)-In a recent paper on the valuation of phosphates according to their citrate-solubility (Chenz.Zeit., xxi ., 905 ; ANALYST, xxii., 334), P. Wagner shows that the phosphoric acid in a citrate-extract of Thomas phosphate can be precipitated free from silica direct by magnesia, without the inter- vention of the molybdenum process, provided that the alkaline citrate and magnesia mixture are added while the extract is fresh. The author claims priority for this observation, as in a paper sent to the Clzem. Zeit. about a month before Wagner’s communication he stated that it was necessary that the citrate solution and magnesia mixture should be added as soon as possible after the extract was ready-at the latest within the same day. Wagner further states in his paper above referred to that it makes no difference whether the ammonium magnesium phosphate be filtered off immediately after stirring, or after standing for two hours.The author, remarking upon this, observes that he has already, in an earlier paper, called attention to three cases in which silica was deposited in citrate-extracts of Thomas phosphate meal on standing for two houxs after precipitation, thus seriously vitiating the results. Though such cases may be rare, it is nevertheless necessary to take into consideration the possibility of their occurring, and therefore the filtration should be carried out promptly. It is also important that the shaking should be commenced immediately after the addition of the citrate solution and magnesia mixture. H. H. B. S. Wagner’s Method for the Determination of Citrate-Soluble Phosphoric Acid in Thomas Phosphate Meal.(Chem. Zed., xxi., 999.)-The author recommends the following procedure : To 50 C.C. of citrate-extract, prepared according to Wagner’s directions, are added 50 C.C. of an alkaline citrate solution (containing in 5 litres, 500 grammes citric acid, and 4 litres ammonia of 0.96 specific gravity) and 15 C.C. of magnesia mixture (conhining in 2 litres, 110 grammes magnesium chloride, 140 grammes ammonium chloride, and 700 C.C. amnionia of 0.96 specific gravity). The solution is shaken for ten minutes, allowed to stand for two hours, or until the following day, and filtered off. When, however, this difficulty is encountered (which is evidenced by the appearance of the precipitate and the slowness of the filtration), the determination is recommenced, and the solution shaken for half an hour and then at once filtered off.I n many cases the author tests the pyrophosphate for silica after weighing by dissolving in hydrochloric acid. B. Sjollema. I n very few cases does any silica, separate. H. H. B. S.THE ANALYST. 83 Gravimetric Method of Estimating Phosphoric Acid as Ammonium Phospho- molybdate. (The American Fertilizer, 1898, in)-To the solution (25 C.C. to 50 c.c., corresponding to 0.25 gramnie of substance) is added 25 C.C. of ammonia of 0.9 sp. gr., and sufficient nitric acid of 1.42 sp. gr. to neutralize the ammonia and produce an acid reaction. The beaker containing the solution is then placed in a water-bath, heated to a temperature of 50" C., and about 10 C.C. excess of ordinary 5 per cent. molybdate solution added from a burette at the rate of about three drops per second, with constant stirring.The beaker is allowed to remain for a further ten minutes in the bath, and the solution is then filtered off throfigh a weighed filter. The filtrate (without the washings) should remain clear, or only show a slight opalescence, on the addition of 5 C.C. of molybdate solution, and further heating for ten minutes in the bath. The precipitate is washed three times by decantation, and three times on the filter with dilute nitric acid (100 : l), followed by one wash with water. The filter is then drained on blotting-paper and dried at 105" C. The presence of so large a quantity of ammonium nitrate ensures complete precipitation, and by the low temperature employed the separation of molybdic oxide or iron salt is avoided.For the final drying at 105" C. a bath containing dilute glycerol (1.160 sp. gr.) is used. Experiments undertaken to determine the exact eomposition of the yellow pre- cipitate dried at 105" C. gave results corresponding to the formula T. S. Gladding. 24Mo03,P,0,,3(NH4),0 + 24Mo03,P,0,,2(NH4),0, H,O + 5 4 . H. H. B. S. On the H. Lasne. describes at Determination of Phosphoric Acid as magnesium I? yrophosphate. (Bull. Xoc. Chim., 1897, xvii., 823-832.)-1n this paper the author length his experiments on the accuracy of the determination of phos- phoric acid by precipitation as a magnesium salt. He finds that rapid precipitation gives an excess of magnesium in the precipitate owing to the partial formation of tri- magnesium phosphate, which only becomes transformed into ammonium magnesium phosphate after contact for sixteen hours with ammonium citrate in sufficient con- centration (10 grammes in 150 C.C.of liquid). It is necessary, therefore, in order to obtain absolutely accurate results, to allow the precipitate to stand overnight. But this source of error is too trifling to lead to the rejection of the well-known rapid method (which the author describes as '' citro-mechanical ") for industrial purposes. The transformation of tri-magnesium phosphate into ammonium magnesium phos- phate is very slow in the presence of ammonium chloride alone, and the amount of citrate mentioned above ought always to be added. The precipitation of magnesium by means of an excess of ammonium phosphate gives at the same time as the arnmonium magnesium phosphate a phosphate contain- ing less magnesium, and the greater the excess of phosphate, the less the magnesium obtained in the precipitate.This is shown in the following tables, in which the results were obtained by dissolving a known quantity of strongly calcined magnesia in hydrochloric acid, and precipitating it as phosphate in the presence of ammonium citrate :84 THE ANALYST. Magnesia taken Corresponding to pyrophos- phate Weight of calcined precipitate 5 c.c, amm. phosph. (10%) obtained with 10 C.C. ,, 9 , 20 C.C. ,, 9 9 A. Gramme. 0.0948 0.2630 0.2687 0.2709 0.2779 B. Gramme, 0.1034 0,2868 0.2929 0.2981 0,3107 Magnesia taken Corresponding to phos- phoric acid Phosphoric acid in the pre- cipit at e obtained with 5 C.C.of amm. phosph. 10 C.C. ,, 9 , 20 C.C. , 9 1 , C. Gramme. OW1034 0.1834 0.1940 0.1971 0.2066 From this the author concludes that the results obtained by this classic method of estimating magnesium are always erroneous. C. A. &I. Separation of Crystallized Silica (War tz) from the Amorphous Variety. G. Lunge and C. Millberg. ( M o d . SC~C~Z~., 1897, [4], xi., 867; through Chem. Zed. Rep., 1897, 324. Also Zeits. aizgezo. Chern., 1897, 393 and 425.)-In spite of Michaelis's statement to the contrary, caustic alkalies cannot safely be employed to separate amorphous silica from quartz, as they dissolve notable quantities of the latter. Even warm sodium carbonate acts quickly and appreciably on quartz when it has been reduced to a very fine state of subdivision. But in a powdered material, which does not contain any real dust, the solvent powers of a 5 per cent.solution of sodium carbonate are almost entirely limited to the amorphous silica; and the maximum error likely to occur during such a separation will be a deficit of 0.1 to 0.2 per cent. of the total silica on the side of the quartz. If silicate minerals are powdered as finely as possible, treated with hydrochloric acid, dried at 110" C., and then digested for fifteen minukes with 5 per cent. sodium carbonate on the water-bath, all the silica set free by the acid will be separated from the quartz and the unattacked silicates, but the amount of the former will probably be 0-2 per cent. too high. They are corn- posed partly of quartz and inactive silicates ; while their active ingredients consist of zeolites and, in particular, of a silicate of sodium and aluminium, resembling analcite, which is completely soluble on the water-bath in 30 per cent. caustic potash. F. H. L. Trass and puzzoliana do not contain any free amorphous silica. The Use of Sodium Oxalate in Acidimetry. S . P. L. Sorensen. (Zeit. anal. Chem, 1897, xxxvi., 639-643.)-Normal sodium oxalate is readily obtained in a pure state by crystallizing the commercial salt from a feebly alkaline solution, washing the crystals with cold water and recrystallizing them. It contains no water of crystal- lization, is not hygroscopic, and can be weighed out very exactly after being dried at 125" C. or even 150" C. The weighed quantity is then converted into sodium car- bonate by moderate ignition in a covered platinum crucible. Sodium oxalate can also be used for standardizing permanganste solutions, and has the advantage over oxalic acid of not efflorescing. C. A. M..
ISSN:0003-2654
DOI:10.1039/AN8982300081
出版商:RSC
年代:1898
数据来源: RSC
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