摘要:

INCLUDING THE PROCEEDINGS OFTHE “SOCIETY OF PUBLIC ANALYSTS.”A Monthly JournaJ for the information of those interested in the purity of Foodand Drugs, aad in generd Analytical and Microscopical Research.[No. 44.1 E$;d { ,. ;gER. NOVEMBER, 1879. [PRICE 6d. ortoswbs@eys annum. P o s t 2 2 . 1G. W. WIGNER,A. H. ALLEN, F.C.S.A. DUPBE, PH.D., F.R.S., F.C.S.C. HEISCH, F.C.S.CONTENTS.J. MUTER, PH.D., M.A., F.C.8.G. W. WIGNER, F.C.S.OXIDATION OF SULPHUR IN CfA8 BY COMBUSTION.OBSERVATIONS ON THE IODIC ACID TEST FOR MORPHIA.NON-EXISTENCE OF NASCENT HYDROGEN ............ 204By W. C. Young,F.C.S ........................... 201By Dr. DiiprB, F.R.S. ............................ 203GAS REGULATORS .................................. 205SPECIFIC GRAVITIES OF FATS, RESIXS, &c.Heger ........................................... 206By Dr.b U M IN BAEINQ POWDER ..........................207NEW METEOD OF PREPARING SmPHURETTEDHYDROQEN .................................... 209CORRESPONDENCE .................................. 210ANALYSTS’ REPORTS ................................ 211LAW REPORTS ...................................... 212NOTES OF TEE MONTH ............................. 217CHEMICAL PATENTS ................................ 2u)BOOKS REOEIYED .................................. 220M. SACEKSON at GO.,65, BARBICAN, LONDON, E J . (nearly opposite the Aldersgate Street Station of the Metropolitan Railway).(J. ORME AND H. M. CAPNER,)FINEST BERLIN ScientificPORCELAIN. Apparatus.BOHEMIA NGLASS.GRA DUA TEDINSTRUMENTS.-HOFMA NN’SAPPARATUS.-ALSOELECTRICAL,GALVANIC,PN EUMA TICA PPA RA TUS,CEC., Bc.Pure GOMPL E 7 tChemicdg. SETS OFQUALITATIVE,QUA N TITA TI YE, -‘ 8 1!: AND ASSAYA PPA RA TUS.-P L A T TN E R’SBLOWPIPE.EGO€ R TZCARBON.ANDTHOMPSON’SFUEL TESTArPARATU SWHOLESALE AND EXPORT.Makers of Apparatus to the Laboratories of the Inland Revenue, Royal &send, Royal MilitaryAcademy, Science Schools, India OfBce, South Kensington, &c.Catalogues and Estimates sent on application, enclosing Business Card for T e r n , &cTHE ANALYST.WORKS BY DR.MUTER, M.A., F.C.S.,President of t h e Society of Public Analysts ; Public Analyst for Lambeth, Southwark,Bermondsey, Rotherhithe, Newington, and Wandsworth.Now ready, demy 8v0, with copious Tables, price 7s.6d.A N INTRODUCTION TO ANALYTICAL CHEMISTRY. For Medicaland Pharmaceutical Students.Now ready, royal 8v0, Second Edition, cloth, with Analytical Tables and copious Index, price 10s. 6d.A N INTRODUCTION TO PHARMACEUTICAL AND MEDICALCHEMISTY, Theoretica and Practical.‘‘ The book is one of a very useful and original kind, and is brought up to the latest date, tests and“ Amongst the best chemical treatises of the day, and in many respects superior to any that have yetprocesses published only a few months since being described in their proper places.”-Chemical News.been published. ”-Pub Zic Health.Third Edition, 600 pp., 8vo. Price 12s. 6d. A KEY TO ORGANIC MATERIA MEDICA.Analytical Chemists willfind this a concise and yet complete book of reference for the isolation and examination of theactive principles of drugs. Special appendix on the microscopic characters of the stwohes in food anddrugs. Copious index and qualitative courses or resins, &c.LONDON : BAILLI~E, TINDALL & Cox, 20, King William Street, Strand, and all Booksellers.By A, WPNTER BLYTH, M.R,C.S,, F.C,S,, Public Analyst for the County of Devon,NOW READY, crown 8v0, cloth, 12s. 6d.PaACTICAL CHEMISTRY (A Manual of). PART I: ANALYSIS OF FOODS-Flour, Bread, Milk, Butter, Cheese; Tea, Coffee, Cocoa; Alcoholic Liquids; Condiments. PART II:“Will be used by every DEWECTION OF PoIsorus-Organic or Inorganic. With Tables and Diagrams.Analyst.”-Lanoet.‘‘ Stands unrivalled for completeness of information.”-Sanitary Record.LONDON : CHARLES GRIFFIN & Co., Stationers’ Hall Court.Bv G, W, WIGNER, F.O.S., one of the Honorasy Secretaries of the Society of Publio Analysts ;Public Analyst for Greenwich, Plumstead, and Woolwich Districts.Price, ONE SHILLING.SEASIDE WATER. An Examination into the character of the Water Supply atthe Watering Places of England and Wales, being an abstract of a Series of Reports prepared forand published in the Sanitary Record during 1877-78, with Three Comprehensive Tables, giving Analysesof the Drinking Water at all the Sea-Coast Towns.KENT & Co., Paternoster Row, London ; and at all Railway Bookstalls.E. CETTI & CO,,MANUFACTURERS OF BAROMETERS, THERMOMEITERS, CHF,MICAL ANDPHILOSOPHICAL APPARATUS OF EVERY DESCRIPTION.Dr.Franklin’s Apparatus for Analysis of Water. Dr. MoLeod’s Modification for Water and Gas.Professor Bischof’s Apparatus for Evaporation of Water. Dr. Sprengel’s Mercurial Air Pumps of everyDrs. Russell and West’s Apparatus for Estimating Urea in Urine. Dr. Blaokley’s Apparatus for Ditto.11 and 31, Brooke Street, Holborn, London, Wholesale and for Exportation, and Rose CottageGlass Works, Pratt Street, Lambeth.form. Water Pumps for quick filtration. Dr. Mill’s Colorimeter.REGISTERED ENAMEL BACK URIN’E SEDIMENT TEST TUBES.THE ANALYST, Vols. I. & III,-(Vol. 11. out of Print.)INCLUDING the Proceedings of the Society of Public Analysts, and embracing alarge number of Original Papers on every branch of Chemical Analysis, with a comprehensiveEdited (under the direction of the Committee of Publication) by G. W. WIGNEB, F.C.S., andJ. MUTER, Ph.D., F.C.S.Published by B A I L L ~ E , TINDALL & Cox, King William Street, Strand, W.C.Index of Subjects and Names. Price, bound is cloth, 7s. ; in half-calf, 9s

ISSN:0003-2654    

DOI:10.1039/AN87904FP045

出版商:RSC    

年代:1879

数据来源: RSC

摘要:

THE ANALYST.PURE ACIDS AND CHEMICALSFOR ANALYSIS.KNOWLES & PHILLIPS,47, MINORIES, E.CPRICE LIST FORWARDED ON APPLICATION.N.B.-References as to quality and price kindly allowed by severalleading Analysts already supplied.THE SILICATE PAINT COMPY.,(FLETCEER, BERDOE & ORR, Proprietors,)‘‘ CARLTON PAINT WORKS,” CARLTON (BY WOOLWICH), KENT.Patentees and Sole Manufacturers of the“ CARLTON” NON-POISONOUS PAINTS AND COLOURS,For House and Ship Painting, Paper Staining, Bcc., &c.The extensive Works of the Company, on the Banks of the Thames, have been greatly enlarged and re-modelled under new management, and in future the QUALITY OF THE GOODS WILL BE GUARANTEED.Sanitary Science impatient of the deleterious substances hitherto in use, called loudly forNON-POISONOUS PAINTS AND COLOURS,And the inauguration of these Works is the response to that demand,NO POISONOUS INGREDIENTS BEING USED IN THEIR MANUFACTURE.The Company’s products are now largely used at home and abroad by Government Establishments,Dockyards, Arsenals, Railway and Shipping Companies, Public Institutions, School Boards, Hospitals,&c., and wherever the laws of health and economy are studied.Their comparatively low price allows of the SILICATE PAINTS AND COLOURS being used forthe commonest as well as for the highest class of Decorative Work.New Descriptive Lists and Pattern Cards are now ready, and may be had, gratis, on application toThe Silicate Paint Company, Carlton (by Woolwich), Kent,Or the Company’s Offices and Depdts-LONDON, 107, Cannon St.; LIVERPOOL, 32, Steel St.; GLASGOW, 21, Hope StTEE ANALYST.THE ANGLO-AMERICAN TIN STAMPING COMPANY, LIMITED,STOURPORT, WORCESTERSHIRE.S E A M L E S S ] PLAIN, RETINNED, AND JAPANNED WARE.MANUFACTURERS OF IMPROVEDSTRAIGHTMILK PAN.The only Company in England producingAmerican and English Patterns of StampedWare by American Machinery.AlsoMOTTLEDDEEPDISH PAN.SAUCEPAN.Sole Licencees, under Letters Patent of August 7 t h 1877, for the Manufacture of WROUGHT-IRONENAMELLED WARE in the United Kingdom.WASH BASIN. ROUND DEEPFLARING PUDDING PAN.MILK PAN.TEE ANGLO-AMERICAN ENAMELLED WARE is a NEW article of Enamelled Wrought-Iron Hollow-mare, differing fromsimilar articles manufactured in Europe in the tenacity with which the enamel clings to the iron upon which it is fused; in thebrilliancy of its glaze ; in the beauty of its ornamentation, due to the colouring oxide supplied by the iron body, which in theenamelling process is absorbed by the glaze and distributed through it in great variety of curious and attractive toms - in thethinness of the enamel, which insures its elasticity, whereby it the better resists fracture ; in the absolute purity an; harm-lessness of the enamel ingredients ; in its perfect insolubility under any action of heat, acid, or water, in culinary operations,which insures ITS ABSOLUTE SAFETY IN USE, as the following certificate will testify :-[COPY] JOHNSON, MATTHEY & CO., Assayers and Melters to the Bank of England, Her Majesty's Mint, &a.Assay Offices and Ore Floors, Hatton Garden, London, E.C.CERTIFICATE OF ASSAY.February8th, 1879.We examined the sample ENAMELLED PANS FOR EXAMINATION AND ANUPSIS, marked as under, and find thefollowing to be the result:The pieces of enamel consist of a silicate of Soda, Blumina, and Lime; entirely free from Antimonv and Lead. Theenamel, as set upon the pans, confirms our experiments with the sample of enamel itself received separately. The pans havebeen subjected to the action both of acetic acid and dilute mineral acids, which they resist perfectly. We consider, therefore,that as enamelled ware it is thoroughly adapted for culinary and domestic purposes.For the Anglo-American Tin Stamping Company, Limited.JOHNSON MATTHEY & CO.The Anglo-American Tin Stamping Co.will be glad to corrospond with buyers regarding special sizes br patterns of goodsfor their markets.Illustrated Catalogue, Prices, and Terms furnished on application, or through any Merchant or Factor.Export Liverpool Agents, HENRY NASH t Co., 12 and 14, Tower Buildings North, Water Street,Export London Agents, BROOKER, DORE & Co., 2, Rood Lane, Fenchurch Street,For the Softening and Filtration of Water in large quantities, within small space, at small cost.The removal of the carbonates of lime and magnesia and iron from hard waters is the removal of(a) The oause of enormous waste of fuel occasioned by incrustation of steam boilers and pipes ;(a) The cause of imperfect cleansing and purification of and injury to linen and woollens in laundries.(c) The cause of the frightful waste of soap, soda, and other alkalies by which those injuries are'imparted and thelmpmities retained.In County Asylums, Steam Laundries, and Manufactoriee ; and for the Town Supply of Old and New Swindon and the RailwayWorks, the Porter-Clark Process is treating hundreds of thousands of gallons per day.The filtration is exquisite, and everything arrested is removed daily.Patented by JOHN HENDERSON PORTER, CEO, 1 & 2, Tudor St., Blackfrim~, London, E.C.ctious IC DISINFECTANT for Preventing Epidemics and DestroANDiseases, as supplied to the Royal Arsenal, Woolwich.This Fluid is a powerful Antiseptic] Disin-fectant and Deodoriser, and from its harmlessness may be applied in any direction without any ill-effects,and with the best possible results.THE '' PRINCESS ALICE" CALAMITY.-The Sanitary Fluid was used at the Woolwich Dock-yard for Disinfecting over 600 bodies.The Clothing taken from the Bodies and over 500 Sheets werealso Disinfected in large Cauldrons. Also the Building, Yards, &c., giving the greatest satisfaction to theDockyard and Parish Authorities. The work was carried out under the superintendence of Mr. HARMXR.SIR,-I beg to inform you thatI consider your Disinfectant, as applied in the Dockyard, both to buildings and clothing, after theremoval of the dead from the premises, very efficacious, and, from its cleanliness and absence of amen,very superior to the Disinfectants in the form of powder generally used.-Faithfully yours, J. T.BARRINGTON, Assistant Commissary General. Mr. Harmer, Stratford, E."For Asylums, Schools, Sanitary Authorities] Railway and Dock Companies, Workhouses, Shipping, &c.Price 1s. per bottle ; 3s. 6d. per gallon ; large quantities at a cheaper rate, of the Sole Manufacturer,W. J. HARMER, West Ham Lane, Stratford, E., or through Agents.The MAGIC FLUID for General Household Purposes, price l a . 6d. per gallon. Write for Pamphletwith Testimonials, &a NON-POISONOUS.Willism Street, Strand, W.C., to whom all communicabions ohodd be addressed.THE SANITARY FLUID.TESTIMONIAL-" H.M. Dockyard, Woolwioh, September 23, 1878.Printed for the Proprietors by JOHN DAVIS, Old Kent Road, S.E. ; and published by B d d R E , TINDdLL Bd COX, m

ISSN:0003-2654    

DOI:10.1039/AN87904BP047

出版商:RSC    

年代:1879

数据来源: RSC

摘要:

201 T THE next Meeting of HE ANALYST. NOVEMBER, 1879. SOCIETY OF PUBLIC ANALYSTS. this Society will be held at Burlington House, Piccadilly, on Wednesday evening, the 19th November. ON THE OXIDATION OF SULPHUR IN GAS BY COMBUSTION. BY W. C. YOUNG, F.C.S. IN No. 8 of THE ANALYST': I published an account of some experiments, made for the purpose of ascertaining whether sulphurous or sulpliuric acid was produced by the combustion of gas containing sulphur, the results of which led me to the conclusion that practically the whole of the sulphur present was converted immediately into sulphuric acid.This conclusion was afterwards borne out by Silliman and Sadler in a paper L L on the volumetric determination of snlphur and ammonia in illuminating gas," which appeared in The Journul of Gus Lighting, vol.29, p. 461, and subsequently by Heisch and Wigner in this journa1.t Having this conviction, it seemed to me possible' to absorb the acid fumes by passing the products of combustion over zinc in a fine state of division, by which means a very simple method of estimating the sulphur would be found as the difference in weight of the apparatus before or after use would be due solely to sulphuric acid.In attempting to put this into practice, I was surprised to find that the zinc was quite unaffected, except in places where moisture had con- densed, and there sulphate had formed. I noticed, moreover, in the course of numerous experiments that wherever sulphate was, there also was carbonate to be found. This result casting some doubt on my former conclusions, I determined to investigate the subject farther, and avoid using any alkaline or basic substance as an absorbent of the acid.Accordingly, I first determined the amount of sulphuric acid contained in the water condensed in the gas referees' apparatus, used without carbonate of ammonia before and after oxidation with nitric acid, when I obtained an average of -5 grainfi of sulphur per 100 cubic feet consumed, but in no case did I find an increase when the liquor was boiled with nitric acid previous to precipitation.As it was possible that the condenser was too hot to admit of the absorption of the acid by the condensed water, I next caused a fine stream of water to flow on to the glass balls in the cylinder by means of a modification of Bischof's constant levcl apparatus, used in his method of water malysis.A drawing of this apparatus will be found in a paper, by me, printed in The Journal of Gas Lighting, vol. 29, p. 464. It consists of an inverted flask, the neck of which is fitted into a tube narrowed towards the end to a fine bore, and fitted near its extremity with a stopcock; on to this tube is blown at right angles another tube bent up again so as to be parallel with the former, and furnished near the top with a stop-cock.To use this apparatus, the flask is filled and the tube fitted firmly into its neck, the whole inverted and the lower stop-cock opened; when the flow of water ceases the delivery can be regulated to any desired rate by means of the upper stop-cock.* VOl. I., p. 43. j- Vol. III., pp. 133, 138.202 THE ANALYST. The following results were obtained in this way :- 1. .. 2. .. 3. .. 4. . * 5. .. 6. .. 7. .. 8. .. Snlphur condensed as HI SO4 in grains per 100 cubic feet of gas consumed. . . . . -90 .. . . . . -65 .. . . . . *80 .. . . . . 1.26 .. . . . . 1.26 .. . . . . 1.31 .. . . . . 1.53 .. . . . . -98 .. Total Snlphur in gas in grains per 100 cubic feet.. . . . 12.9 . . . . 14.8 . . . . 11.9 . . . . 12.8 . . . . 15.4 . . . . 14.6 . . . . 12.7 . . . . 13.2 It seems, therefore, that either by using a larger quantity of water, or by cooling the cylinder, the amount of sulphuric acid condensed was somewhat increased but not to the extent expected, as fully half the space in the cylinder was kept quite cool during the progress of the experiment.This experiment was varied by carrying the end of the eduction tube of the referees’ apparatus into the neck of another cylinder, on to the glass balls in which the water was run, so that the condensing power of the apparatus was vastly increased whilst using the same quantity of water as before, The results thus obtained are as follows :- Sulphur condensed as HP SO* in grains per 100 cubic feet of gas consumed.Total Sulphur in gas in grains per 100 cubic feet. 1. . . . . . . 1.02 . . . . . . 12.8 2. . . . . . . 1.01 . . . . . . 16.1 A second estimation of the sulphur in the liquor obtained in these experiments was made after oxidation, but no increase was obtained. It was clear, therefore, that the meam adopted were inadequate for the purpose of the complete absorption of the sulphur acids formed, but it seemed to me that if only sulphuric were formed these means were competent to arrest i t ; and to assure the presence of that acid only, I substituted bromine water for the water, using only one condenser, when the following results were obtained :- Sulphur in grains per 100 cubic feet Total Sulphur in gas in grains of gas consumed.per 100 onbic feet. 1. . . . . . . 3.28 . . . . . . 13.8 2. . . . . . . 5-20 . . . . . . 12.4 3. . . . . . . 8.22 . . . . . . 13.1 In these experiments the sulphur obtained as sulphuric acid increased with the bromine water employed, which in the last one was a saturated solution ; as, however, a considerable portion of the sulphur had escaped condensation, a trial was made with the double apparatus before described, substituting bromine water for the water, when very similar results were obtained, as will be seen below :- Sulphur obtained in grains per 100 cubic Total Sulphur in grains per 100 cubic feet of gas.feet of gas consumed. 1. . . . . . . 7-25 . . . . . . 10.80 2. . . . . . . 7.32 . . . . . . 9.48 It being evident that sulphuric acid could be absorbed from the mixture of gases by means of water, the inference &awn from the failure to obtain the whole of the sulphur was that the remainder escaped in the form of sulphurous acid, the means employed not being sufficient to oxidise the whole; accordingly I again varied the experiment by placing bromine under water beneath the burner, dispensing with the dripping apparatus, and substituting a reservoir of bromine under water in the upper cylinder, formed by removhg the tube in the bottom and plugging the hole.THE ANALYST.203 In this way I obtained more sulphur in the form of sulphuric acid, per 100 cubic feet of gas consumed, than was given by the method employed for estimating the total quantity of that impurity in the gas, as will be seen below :- Sulphur as HI SO* found by experiment as above Total Sulphur in gas by “ Referees”’ described in gas per 100 cubic feet of gas. method in gas per 100 cubic feet.1. . . . . . . 14.2 . . . . . . 12.5 2. . . . . . . 13.8 . . . . . . 12.4 3. . . . . . . 12.5 . . . . . . 11.3 As some of the sulphur obtained may have been derived from the vulcanized rubber connections employed in these experiments they were repeated, cork being substituted for the rubber, when the results obtained were practically the same as those given by the usual method of estimating the sulphur.Repeat of last experiment, cork connections substituted for vulcanized rubber :- Sulphur 8s HI SO, in grains per 100 cubic feet. Sulphur by ‘‘ Referees’ ’’ method in grains per 100 cubic feet.1. . . . . . . 13.00 . . . . . . 13.4 2. . . . . . . 9-28 . . . . . . 9-2 3. . . . . . . 13.20 . . . . . . 13.3 These results show beyond doubt that sulphurous acid only is formed when gas is burned in aBunsen burner under the ‘‘ Gas Referees’ ” apparatus, as the small quantity condensed as sulphuric acid by water alone may reasonably be assumed to have been oxidised during its passage through the aparatus.It is remarkable, however, that h all the experiments I have made where alkali or alkaline carbonate was used as the absorbent no trace of sulphite could be detected; that sulphurous acid cannot be detected in the water condensed in the cylinder, by the ordinary tests, and that when the cylinder is packed with zinc, or copper turnings, the whole of the sulphur is arrested, the resulting compound being invariably sulphate, and especially so in face of the circumstances that the air in the apparatus was formed to contain, on an average, only 12 per cent.of oxygen when the gas was burning at the rate employed, which was *Ei cubic feet per hour ; but if any doubt could have remained as to the power of the current of hot air to oxidise the alkaline and other sulphites formed (by the action of sulphurous acid on carbonate of zinc or copper), the result of the following experiment must have entirely removed it. An alkaline solution of sulphite of soda, containing the equivalent of 5 per cent. of sulphur, was slowly run on to the glass balls in the cylinder of a Gas Referees’ sulphur apparatus, the flame of a small spirit lamp being employedin the place of a Bunsen burner to produce the current of air, when it was found that the whole of the sulphite was oxidised into sulphate before it reached the bottom of the appmatus.

ISSN:0003-2654    

DOI:10.1039/AN8790400201

出版商:RSC    

年代:1879

数据来源: RSC

摘要:

THE ANALYST. 203 SOME OBSERVATIONS ON THE IODIC ACID TEST FOR MORPHIA. (Abstract of Paper by DR. DUPR~, from Guy’s Hospital Reports, of 1863). Test solution empbyed-Iodic acid, 1 part in 15 parts water ; starch, 5 grains boiled with 2,000 grains of water ; ammonia, ordinary strength as used in testing, and the tame diluted about 50 times. Solutions of morphia or its sa,ltB, as nearly neutral as possible, give a yellow colour&tion, on addition of iodio acid ; a tint is still perceptible when 1 part of morphia204 THE ANALYST.is present in 20,000 parts of solution. As long as the dilution is not greater than 1 in 600, a blue colouration is produced on addition of starch ; below this strength the pro- duction of the blue becomes uncertain, and it fails altogether to make its appearance if the dilution exceeds 1 in 1,000.In the case of ordinary reducing agents, the blue iodide of starch is produced, even if they ard so diluted that the yellow colouration, due to the iodine liberated from the iodic acid, is no longer perceptible. If to the mixture of iodic acid and morphia solutions an excess of ammonia is added, the yellow colouration produced by the iodic acid is, as shown by Lefort, considerably increased in intensity, and the colouration may, under these conditions, still be perceived in solutions holding no more than 1 part of morphia in 30,000 parts of solution.The colouration produced in ordinary reducing agents is discharged by ammonia. As stated above, mixtures of iodic acid and morphia, containing less than 1 part of morphia in 1,000 parts, no longer become blue on addition of starch.If, however, a very dilute solution of ammonia be carefully poured on to the surface of this mixture, which is best done by means of a fine pipette, two coloured rings make their appearance at the junction of the two fluids. A blue ring becomes visible in the lower acid layer, and a brown one in the upper alkaline portion ; when the two layers are mixed the whole assumes a brownish colour. In this way the blue ring may be made visible in solutions containkg only 1 part of morphia in 20,000 parts of solution. If a drop of the mixture of morphia and starch is carefully evaporated on a piece of white porcelain, and the dry spot, after cooling, is moistened with iodic acid, as little as 1-20,OOOth grain of morphia may be recognised by the blue colouration produced.

ISSN:0003-2654    

DOI:10.1039/AN8790400203

出版商:RSC    

年代:1879

数据来源: RSC

摘要:

204 THE ANALYST. * THE NON-EXISTENCE OF NASCENT HYDROGEN. BY DR. DONATTO TOMMOSI. THE author has proved by very ingenious experiments that the so-called nascent hydrogen does not differ in any respect from ordinary hydrogen. Of the vmious experiments we will mention the most important. 1. A solution of chlorate of potash was treated for some time with sodium amalgam. The liquid was then neutralized with nitric acid and tested for chlorine with nitrate of silver, but no chloride of silver was produced, showing the nascent hydrogen does not reduce the chlorate.2. The experiment was repeated, but this time with constant addition of some acetic acid to keep the liquid slightly acid. After six hours the liquid was tested with nitrate of silver, and found to be free from chlorine, 8.A saturated solution of potassium chlorate was acidulated with sulphuric acid and divided into two parts. The one was treated with zinc and the other with aodium amalgam. The fluids were both filtered before the free acid was neutralized. They were ,then both tested for chlorine. The one treated with the sodium did not precipitate with the silver, but the other gave a copious precipitate.It may now, perhaps, be thought the reduction of the cldorate was due to the nascent hydrogen evolved by the action of the zinc on the sulphuric acid, but the following experiment proves the reduction may be due, partly at least, to the zinc alone. Journal Les Nondes, T. XLVIII., No. 7.THE ANALYST. 205 A very weak solution was so slightly acidulated with sulphuric acid as scarcely to act upon zinc.This solution was put into a U tube and decomposed by a galvanic battery, composed of eight Bunsen elements. The negative electrode consisted of platinum foil; the positive one of zinc foil. After two hours a little of the liquid (zinc side) was tested for chlorine, and it gave copious precipitate with silver, the other (platinum side) did not contain a trace. So from the experiment it appears that even electrolytic hydrogen does not reduce the chlorate, but the reduction was caused by the zinc.In order to prove this still more conclusively the experiment was repeated with a platinum electrode instead of the zinc one, and no trace of chloride was produced even after 20 hours. The author found it impossible to reduce perchlorate of potash with so-called nascent hydrogen prepared by any of the known methods. Whenever so-called nascent hydrogen reduces, it is because it happens to be accompanied by a sufficient amount of heat evolved during the chemical action of the substances which yield the hydrogen, but not because it possesses other properties than ordinary hydrogen. The author also considers it highly improbable the nascent hydrogen should consist of isolated atoms of H.

ISSN:0003-2654    

DOI:10.1039/AN8790400204

出版商:RSC    

年代:1879

数据来源: RSC

摘要:

THE ANALYST. 205 GAS REGULATORS. A NEW form of gas regulator, or governor, originally designed merely for application to street lamps, has been brought under our notice. It appears to possess special advantages for laboratory use in the perfection with which it regulates the supply of gas under varying pressures. The inventor, Mr. Borrodaile, has discarded the ordinary flexible diaphragm, and constructs the governor entirely of metal.For sizes constructed to pass five feet or less per hour, the apparatus consists of a small brass cell carefully turned inside. The diameter of the cell is nearly that of an ordinary shilling, and it is about one-third of an inch deep. The inlet and outlet pipes for the gas pass into the top and bottom of the cell. The only movable part is a thin flat metallic disc, turned so as to fit the cell accurately, though loosely enough to vibrate freely.This disc carries a short metallic tube about a quarter of an inch long, which serves as a guide to ensure the parallel motion of the disc, and also as the tube through which the gas passes from the lower part of the cell to the upper. The regulation is effected by the rising or falling of the disc.When the pressure rises, this disc, carrying with it the metallic tube through which the gas passes, rises also, and by bringing the end of the tube nearer to a fixed plate, partially cuts off the supply of gag, similarly, when the pressure is diminished, the plate falls and the gas way is increased. Simple as the invention is, it works better than the ordinary governors, as the following experiments will show.Three burners, nominally four feet, were attached to the same pipe, under a gas pressure of 9-lOths of an inch. The consumption of the three was 11.7 feet per hour, or an average of 8.9. The gas pressure was suddenly increased to 19-l0tha, and it was impossible to detect any difference in the illuminating power.206 THE ANALYST.One governor with burner attached was tested separately. Under a pressure of 9-lOths inch it passed 3.87 C.F. per hour. 9 , ,, 19-l0ths ,, ,, 3'82 ,, The orifice of the burner (an ordinary batswing jet) was reduced to less than half its area by putting a thick piece of paper in the slit. Under a pressure of 9-l0ths inch it passed 3.85 C.F. per hour. 9 9 ,, 19-l0ths ,, ,, 3.80 ,, A test was made another day at higher pressures, and the following results were obtained : - Under pressure of g-lOths, a burner passed 3.80 C.F.per hour. Y Y ,, 30-10ths, ,, t , 3.70 9 ) $ 9 ,, 50-10ths, ,, 3, 3-67 7 9 Another governor, made to pass more than 30 cubic feet per hour, was connected with four of the largest-sized Bunsen burners and used to heat a steam bath. Under a pressure of 19-lOths the consumption was, when all four burners were turned on, 33-ft. per hour; when only one burner was turned on, 32.5-ft. per hour. We have been using it very successfully for regulating the supply of gas to air drying baths, and are testing it for regulating the currents of air in gas washing experiments. In will be found valuable in the laboratory in many other ways.

ISSN:0003-2654    

DOI:10.1039/AN8790400205

出版商:RSC    

年代:1879

数据来源: RSC

摘要:

206 THE ANALYST, SPECIFIC GRAVITIES OF FATS, RESINS, ETC. BY DR. H. HAGER. The author first describes a simple method for determining these specific gravities. This consists in melting the respective fat, dropping it into a flat-bottomed vessel containing alcohol, in such a manner that the point from which the drops are allowed to fall is not over three centimetres distant from the surface of the alcohol, and that each drop be allowed to fall on a different spot. The fat globules thus deposited at the bottom are then removed to a liquid, consisting of either alcohol, water or glycerin, or mixtures of these, until after careful stirring and reduction or increase of the density, by the addition of one or another of the above liquids, the fat globules are held in equilibrium in any part of the liquid.The specific gravity of the latter is then determined, and this is, of course, at the same time the specific gravity of the fat. The author then gives a list of specific gravities, which is here reproduced :- Butter Fat, clarified by settling .. 7 7 several months old . . . . . . . . Brtiilcial Butter . . . . . . . . . . . . Hog’s Lard, fresh .. . . . . . . . . . . ,, ,, old . . . . . . . . . . . . Beef Tallow . . . . . . . . . . . . . . Sheep’s Tallow . . . . . . . . . . . . Beef and Sheep’s Tallow, mixed 1:l Butter of Cacao, fresh . . . . . . . . . . , Y very old 7 7 and Beef Tallow, mixed 1:l . . . . . . . . Expressed Oil of Nutmegs . . . . . . . . . . 7 7 7 7 ,) extracted with carbon disulphide s7 7 , adulterated with fatty acids .. . . . . . . . . . . . . . . .. . . . . . . . . . . .. .. .. .. .. .. .. .. .. .. .. .. .. .. sp. $r. at 15-l& c. .. 0-938-0940 .. 0 9 3 6 4 9 3 7 .. 0.9244930 . . 0*931-0*932 .. 09254.929 .. 0.937-0-040 .. 0.936--0*988 . . 0*950-0*952 .. o . o ~ - m 4 a . - 0.945-0.946 . . 0938-0.939 . . 1*016-1.018 . . 1.014-1.015 . . 1 ~ 0 1 ~ 1 ~ 0 1 1THE ANALYST .207 Sp . gr . at 15-16Q C . Expressed Oil of Nutmegs. crystalline . . . . . . . . . . 0965-0.966 Stearic Acid. melted and in drops . . . . . . . . . . . . 0964 . . . . crystalline . . . . . . . . . . . . . . . 0.967-0.969 Wax. yellow . . . . . . . . . . . . . . . . . . 0.959-0.962 .. African . . . . . . . . . . . . . . . . . . 0.960 .. yellow and resin. mixed 1:l . . . . . . . .. . . . 0.973-0-976 . . . . and paraffin. mixed 1:l . . . . . . . . . . 0.916-0919 . . . . . . yellow ceresin. mixed 2:l . . . . . . . . 0-942-0.943 Ceresin. yellow . . . . . . . . . . . . . . . . 0.925-0928 Wax. Japan . . . . . . . . . . . . . . . . . . 0.977-0-978 . . . . very old . . . . . . . . . . . . . . . . 0.968-0.970 .. white. very old and true . . . . . . . . . . . . 0.963-0.964 .. . . new . . . . . . . . . . . . . . . . 0.916-0-925 . . . . . . and stearic acid. mixed 1:l . . . . . . . . 0.945 Wax. sp . gr . 0.963 and stearic acid. sp . gr . 0.963 mixed 1:l . . . . 0975 Ceresin. very white. pure . . . . .. white . . . . . . . . Araucaria Wax . . . . . . Resin (fr . pine). yellow transparent .. .. whitish. opaque . . . . .. very dark colophony .. Shellac. light coloured . . .. darker . . . . . . .. bleached . . . . Dammar. old . . . . . . Copal. East Indian . . . . .. West Indian . . . . .. very old . . . . Benzoin. Siam . . . . .. Penang . . . . .. Borneo . . . . Guaiac Resin. pure . . . . Amber . . . . . . . . Sandarac . . . . . . Mastic . . . . . . . . Balsam of Tolu. old brittle . . (Kamala . . . . . . (Lycopodium .. . . . . Many of these figures may bodies.-New Remedies . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.905-0.908 0.923-0.924 0.990 1*083-1.084 1*044-1-047 1.100 1.1 13-1.1 14 1.123 1.075 0.965-0.968 1.063 -1.070 1.070-1.800 1.054-1*055 1.235 1.145-1.155 1*165-1.170 1.236-1.237 1.074-1.094 1.038-1*044 1.056-1*060 1.231-1.232 1.115-1.120) 1*016-1.020) be used as criteria for distinguishing the various

ISSN:0003-2654    

DOI:10.1039/AN8790400206

出版商:RSC    

年代:1879

数据来源: RSC

摘要:

THE ANALYST. 207 ALUM I N BAKING POWDER. IN a recent issue of the Scientgc American Supplement will be found a communication from G. E. Patrick, Professor of Chemistry in the University of Kansas, giving details of a series of practical tests to determine whether the hydrate of alumina is dissolved by the gastric juice. The question has avital bearing on the discussion as to the safety of using alum in baking powders.Professor Patrick attacks it without prejudice, by strictly scientific methods, and arrives at results which are certainly gratifying in view of the wide use of alum powders in our kitchens. Professor Patrick takes his text from the published opinion of a prominent physician who says, after stating the difficulties attending a thorough mixture of the hgredients of alum baking powders :--" But even if the exact proportions were maintained, the208 THE ANALYST.salts formed would retain their injurious properties, as they would dissolve in the gastric juice. The gastric juice contains not only lactic acid, but a large amount of hydrochloric acid, and both the sulphate and hxdrate of alumina would be dissolved. ” After testing by reference to authorities the statement that the gastric juice contains a large amount of hydrochloric acid, and finding the weight of evidence to be that the quantity is in reality extremely minute, and that little not free, Professor Patrick proceeds b describe his examination of the practical question whether the hydrate of alumina.as it exists in bread after baking, when made with alum powders, will be dissolved in the fluids of the alimentary canal.This question could be determined only by careful tests with living animals. Professor Patrick found cats to be most available. Having made biscuits with an acknowledged alum baking powder, using twelve times the proportion of powder directed on the labels, and employing for each experiment a distinct sample of powder, he fed the biscuits to cats that had fasted from one to two days.The amount eaten in each case was enough to give at least half a teaspoonful of powder to each experiment. After allowing for digestion 20 minutes, 45 minutes, 18 hours, 2 hours, and 2+ hours, respectively, the cats were killed, and the contents of the stomach and small intestines were carefully examined for dissolved alumina. In each case undissolved hydrate of alumina was found, but of dissolved alumina there was never a trace.Surprised at the uniformity of these results, and thinking that the organic matter of the flour might have interfered with the solution of the alumina or his detection of it, Professor Patrick made two crucial experiments. In each, two teaspoonfuls of the powder were mixed with water and baked at the ordinary temperature of the oven.The mass was then fed to a cat (under compulsion) and after a specified time the stomach and intestines were examined as before. In neither case was a trace of dissolved alumina discovered. Similar experiments were then tried with unbaked (gelatinous) hydrate of alumina, and in these cases a trace of dissolved alumina was found; the inference being that it is not safe to eat dough made with alum powder-it should always be baked.Another important practical point was also suggested-namely, that if bread is carelessly mixed or with insufficient water, some of the powder may remain dry and the alum not changed to the hydrate ; in which case the effect would probably be injurious.In order to test this question, and also to furnish a check on the other experiments with biscuits, Professor Patrick had a batch made in which the mixing was less thorough than usual and with less water. These were fed to cats, and subsequent tests developed in every case a trace of dissolved alumina. These experiments, while proving the reliability of those first described, go to show, Professor Patrick thinks, that to insure the entire absence of alum in the bread, the mixing must be done with plenty of water. As a simple precaution it might be well to mix the batter too thin at first, and stiffen it by the addition of pure flour.z:--New Remedies. Mr. J. Baynes has been appointed Public Analyst for the Borough of Boston. * We do not find, however, that Professor Patrick’s experiments contain any reference to the effects which might be produced by the insoluble alumina.- [Eds. ANALYST.]

ISSN:0003-2654    

DOI:10.1039/AN8790400207

出版商:RSC    

年代:1879

数据来源: RSC

摘要:

THE ANALYST. 209 A NEW METHOD OF PREPARING SULPHURETTED HYDROGEN. By J. FLETCHER, F.C.S., London and Paria. ANY mode by which the preparation of this useful gas can be rendered easier, and the unpleasantness of its manipulation diminished, will no doubt be welcomed by analysts : I therefore make no apology for submitting the results of some experiments made after reading a suggestion in some of the scientific journals, perhaps your own, but the name does not at the moment occur to me.The plan is simply to fuse in a small glass flask sulphur and solid paraffin, leading the resulting gas by meam of a perforated cork, india-rubber, and glass tube directly into the solution to be tested. The first gases are not sulphuretted, but when the mixture has been thoroughly fused and mixed the sulphuretted hydrogen passes over abundantly.The advantage of the process is that the moment the flame of the lamp is removed the evolution of gas ceases, and the little apparatus can be laid aside without fear of creating offensive smells. When used again, the gas passes at once when sufficiently heated. I passed the gas for an hour through such a bottle, and the water, although most strongly impregnated with the gas, was fairly clear and limpid, showing only the usual appearances.There are a few precautions to be taken. The mixture is inclined to bump when strongly heated, but a few pieces of broken tobacco-pipe shank prevent that. Care must be taken that when the lamp is removed, and the gas ceases to pass, that none of the solution is sucked back into the bulb ; it is very easily prevented.A very strong heat should not be applied, as then distillations would commence and the product condense in the tube. I believe the process to be a simple, cleanly, and elegant substitute for the old methods, and particularly well suited for small and private laboratories. How it would work in large ones I would like to hear from those who are in a poaition to try it.- Chemical News.A washing bottle seems unnecessary. Referring to the above note the following letter has appeared in the Chemical Nt?ws :- To TEE EDITOR OF “THE CEEMICAL NEWS.” Sm,-h the Chemical News, vol. xl., p. 154, Mr. J. Fletcher has described what he calls a new process for the pPeparation of H,S by melting sulphur and solid paraffin together.Allow me to state that the process is not new, having been used by myself and others as far back as 1872. I continued to use it for more than twelve months, but found it very unsatisfactory, because of its expIosive qualities, and upon that account gave it up. As far as I remember an explosion took place about every seventh experiment; at one time the cork of a flask would be violently ejected and the contents sent to the ceiling, at other times the flask was completely destroyed. The procese works remarkably well except for this one fault, and if Mr. Fletcher has succeeded in overcoming its explosive qualities by the addition of broken tobacco-pipe shanks he has indeed rendered a service to chemists in general. I am, &c., WILLIAM JOHNSTONE, F.I.C., F.C.S. WieBbaden, September 29th, 1879.

ISSN:0003-2654    

DOI:10.1039/AN8790400209

出版商:RSC    

年代:1879

数据来源: RSC

摘要:

210 THE ANALYST. CORRESPONDENCE. [The Editors are not rcsponsible for the opinions of their Correspondents.] To THE EDITOR OF “THE ANALYST.” SrR,-If we are to believe some of our would-be teachers, there are-to paraphrase one of Carlyle’s well-known sayings-in these islands about a hundred Public Analysts-mostly fools. Under these melancholy circumstances, the Pharmaceutical Society has apparently undertaken the task, through its paid professors and editor, of educating us €or our work.Unfortunately, no doubt owing to my belonging to the majority, I often fail to understand either the chemistry, the sense, or the morality of the teaching. Can any one belonging to the minority enlighten me ? In the Pharmaceutical Journal for September 27th, I find Dr. Paul reported as stating in evidence, that “ the presence of tartrate of lime in cream of tartar was indicated by the Byitish Pharmacopaia; ” and in an editorial article in the same number it is said, that the fact that tartrate of lime is a natural ingredient of cream of tartar is recognised in the British Plwmnacopaia.Now, bearing in mind that the evidence was given in defence of a person accused of having sold cream of tartar adulterated with 11.7 per cent.of tartrate of lime, I turn to my British Phaimacopaia, and what do I find? That the presence of traces of a calcium salt, not specially of tartrate of lime, in cream of tartar is recognized, and that traces only are meant, is placed, as I read the book, beyond a doubt, by both the qualitative and the quantitative test given.Professor Redwood’s letter on this subject is, I must confess, beyond my powers of understanding ; but it requires I suppose the highly-trained intellect of a pharmaceutical chemist for its comprehension. In the number for October 18th, I find among other the following evidence of Professor Attfield reported. ‘‘ On account of the rapidity of the manipulation of the work by the boy in putting the soda into the bottles, I should certainly expect the quantity to vary from say & of a grain to 3 or 4 grains.” Why not from nothing to-.No doubt the poor milkman is often punished, because in his hurry he has merely forgotten to empty his can of the water he used in washing i t ; and the poor grocer because he has ground first chicory and then coffee in the same mill, and has simply forgotten to clean it between the operations, &c., &c.The soda dropped into one ‘of the bottles falls on the glass ball, sometimes partly, sometimes mainly; and then, when the water charged with gas is driven by the machine into the bottle, air and gas escape from the neck of the bottle, and with that air nearly always comes out some spray, and with that spray might come a certain amount of soda.” What may not have been carried away by that spray ? ‘‘ I then pressed down the ball and got out the liquid, and found lead therein. I immediately examined the particles of wax for lead, and found lead in considerable quantity .” Astonishing ! When asked, ‘‘ Do you consider the lead in the sample innocuous ? ”-he answers, ‘‘ Perfectly ; such a minute quantity must be.” Would Professor Attfield be kind enough to give us the exact composition of the residue left by this sample of soda water ; and also the method which enabled him to state, positively, that the water contained about a 2 of a grain of added soda per bottle? Also, would he inform us whether, in his analyses and reports on potable water, he considers 1-20th of a grain of lead per gallon as necessarily innocuous ? In the same number (18) the certificate of the analyst is given, in which it is stated :-‘‘ This sample ie ardinary water charged with carbonic acid gas, and does not contain added bicarbonate of soda, and is not soda water.” In his evidence, Mr.Thomas is reported to have stated in answer to the question : “ Supposing it contains only 3 grains ? ”-“ It would still be soda water.” But what says the editorial article? “The Newport analyst followed the example of many of his brethren in arriving at the conclusion that the British Phimacop@ia furnished a standard for the composition of soda water,- that if it did not contain in the half-pint 15 grains of carbonate of soda, it was not of the nature and quality of ‘ soda water.’ ” But enough for the present ; and, in conclusion, I would only ask : Are we to accept such teaching as the above ? Are pharmaceutical chemists trained in this way to supplant the ‘ too often incompetent Public Analyst ? ”--vide Professor Tilden’s speech before the Pharmaceutical Society, October lst, 1879; and, finally, does the Council of the Pharmaceutical Society sanction and approve this kind of teaching ? “ There was enough soda to warrant the name-it was about & of a grain.” Yours truly, A.DUPRdTHE ANALYST. 211 THE IODIC ACID TEST FOR MORPHIA. To THE EDITOR OF “ THE ANALYST.’’ Sm,-When writing a note upon the above last month, I find I was mistaken. I was under the impression that ammonia was to be added to the bisulphide of carbon containing the dissolved iodine ; instead of that, the ammonia is to be added to the iodic acid and morphia. Dr. Duprh kindly called my attention to the error which I had fallen into, and also referred me to & paper which he had published upon this subject some years since, no notice of which I believe has been taken in any of our text books. I consider Dr. DuprB’s paper a model of clear statement ; one cannot well fall into error with such a guide ; it would be well if our text books on analytical chemistry were as clear. I have been carefully over his paper and the results are as stated. Yours truly, J. CARTER BELL,

ISSN:0003-2654    

DOI:10.1039/AN8790400210

出版商:RSC    

年代:1879

数据来源: RSC