CHEMICAL NEWS, June 6, 1919 NOTES. Notes from Foreign Sources, AN interesting paper on the " Occlusion of Hydrogen by the Metallic Elements," by Donald P. Smith, is given in the Journal of Physical Chemistry for March, 1919. The results of a very complete search of existing literature are embodied in tabular form, and the conclusion of the author that the capacity of a metal to occlude hydrogen is con. nected with its magnetic character is best given by the Summary that follows the paper:-"From a review of the literature relating to the occlusion of hydrogen by the metallic elements it is shown that the resulting alloys are clearly to be distinguished from other types of binary hydrogen compounds, and that the metals which form the alloys probably occupy a definite region in the periodic table of Werner. The metals of this region are classified into those which do, and those which do not, occlude in a degree measurable by the ordinary volumetric method. From a comparison with magnetic data it is shown that the occluding and non-occluding elements, excepting copper, rhodium, and thorium, are identical with those for which the specific magnetic susceptibility possess a value respectively greater or less than about +09. 10-6 at room temperature. It is concluded that the capacity of a metal to occlude hydrogen in large degree is an accompaniment of strongly magnetic character." THE "TANK."-We are indebted to Major-General E. D. Swinton for an account of the origin of this con trivance about which so much bas been said and written, and which undoubtedly contributed largely to the successful termination of the war. The account was given at an informal dinner following the general meeting of the Institute of Mining and Metallurgy on April 10 last. We quote the Major's own words :-"In July, 1914, Mr. Marriott wrote from Antwerp-where his job at the moment was trying to find out some cheap and efficient form of transport across rough country for mining pur poses. He knew all about rope railways, telpherage, narrow gauge railways, and so on, and informed him that in Antwerp he had seen an American caterpillar tractor which would go over rough country and climb like hell.' This, it must be remembered, was before the war. He (General Swinton) happened to be in a position then when he could approach different departments; in vulgar language he was a sort of Buttinski, and he was able to go to the War Office and the Admiralty and tell the people Concerned that there was an American tractor in Antwerp which would, in the coarse words of his friend,' climb like hell,' and that it was up to them to investigate it for tractive purposes. The machine referred to was the Holt tractor. Shortly after that he had gone out to the war, as he had said just now, as a journalist, and his position gave him an opportunity of seeing and learning a lot. It was then that he became convinced that a machine which could climb like hell was a thing not to be lost sight of, and if it could be developed or improved into a bullet-proof machine which could climb to beat hell' they had something which might meet the German machine guns." AT a recent meeting of the Society of Public Analysts and other Analytical Chemists a paper was read by Helen Masters, B.Sc., on "Soluble Lead in the Glaze of Casseroles." Attention was drawn to the extended use of glaze vessels for culinary purposes and to the danger that food cooked in such vessels might become contaminated with lead. In Germany the sale of vessels which yield any soluble lead on boiling for thirty minutes with a 4 per cent solution of acetic acid is prohibited. Experiments with various glazed vessels show that in some cases a considerable amount of lead can be extracted from the glaze, not only by the action of 4 per cent acetic acid, but also by the action of more dilute solutions of organic acids, e.g., I per cent acetic, citric, or malic acid. In some cases as much as from 2 to 4 mgrms. of lead 275 monoxide per square decimetre was extracted by a 1 per cent acetic acid solution in thirty minutes, and in an exhaustive experiment of this kind as much as 28.7 mgrms. of lead monoxide per sq. dem. was extracted by twelve successive boilings. The danger of the use of such vessels is very real, and manufacturers would do well to have reliable tests made of their wares so as to avoid the use of soluble glazes; the expense would probably be well repaid by marking their wares with a guarantee of their insolubility. WE have received a copy of the first number of a new publication, the Italian Gazette, a financial, commercial, and economic review, a quarterly journal, edited by Roberto Lombardo, with Edward Storr, as sub-editor; published at Piazza Cavour 17, Rome. The matter opens with a message of appreciation from the British Ambassador, Sir Rennell Rodd, and the object is to improve and strengthen the relations of sympathy and friendship between England and Italy that have become so apparent during the War. In a brilliant introductory article by Luigi Luzzatti the need for an intimate friendship between Italy and England is developed. Other articles on financial and commercial matters by prominent Italians appear, and in all of them there is to be noticed a sincere desire for the friendly relations between us to be expanded for our mutual benefit, and an avowal of their distrust of Teutonic methods in commercial and other circles that has been brought home to them as to other nations by recent developments. We wish the new publication every success. Our only regret is that it is not to appear at more frequent periods than once a quarter. NOTES FROM FOREIGN SOURCES Stability of Javel Extracts.---M. Fonzes-Diacon.Javel extracts, when kept, lose considerable quantities of active chlorine, the loss being caused principally by the action of light and the author has made a study of the course of the reaction and the conditions which may lead to its reduction to a minimum. Eight samples were exposed to the action of diffused light by putting them before a well lighted window on which direct sunlight was not falling; two were placed in flasks made of yellow glass, one of a much darker shade than the other, and the six others in white glass. The chlorine was determined at intervals of time extending over about four months, and it was found that even in that time the loss of chlorine in the dark yellow flask was very small; in the less deeply coloured glass it was rather greater and still more marked in the white flasks. The greater the proportion of active chlorine the greater the loss, and after four months' exposure to the action of light extracts which originally contained very different amounts gave results which approached a common limit. If the initial amount of active chlorine present is about 5 grms. per 100 cc., and if the extracts are kept in dark yellow flasks, they may be regarded as unaltered at the expiration of several months. Bull. Soc. Chim. de France, 1919, xxv.-xxvi., 206. Analysis of Antimony Salts.-Various methods have been suggested for the analysis of antimony sulphide, which may contain free sulphur, antimonic acid, antimonates, red antimony sulphide, antimony oxysulphides, or calcium sulphate. The oldest methods of determining the amount of free sulphur depended upon the extraction of it by carbon disulphide, using a Soxhlet's apparatus, and it has recently been found that the pentasulphide is practically unattacked in the cold, and even on warming only about 0'4 per cent is reduced. Benzene or acetone can be used as solvent, but if benzene is used the pentasulphide must previously be thoroughly dried. Acetone is not to be recommended, for it dissolves a small quantity of the sulphide in addition to the free sulphur. Another method of determining the impurities depends upon the fact that antimony pentasulphide is completely soluble in warm ammonia, and the other substances present can be filtered off and determined in the usual way. To estimate the total sulphur the sulphide can be dissolved in a solution of pure potash and then subjected to the action of chlorine, when all the sulphur is transformed into sulphuric acid and the antimony into antimonic acid. Fuming nitric acid can also be used to convert the sulphide into sulphate, which can be estimated as barium sulphate in the usual way, and hydrogen peroxide acts similarly. If the sulphide is dissolved in pure sodium sulphide the percentage of antimony present can be determined by electrolysis, platinum electrodes being employed; but this process cannot be recommended, for the values obtained are always too high. By treating a solution of the sul Chemist, demobilised, three years' Technical College training and one year works experience, in order to regain experience, lost Army service, would communicate with Analyst of extensive practice with view to Post as Pupil Assistant for limited period.-Address, R. B., CHEMICAL NEWS Office, 16, Newcastle Street, Farringdon Street, London, E.C. 4. hemist, three years' experience in large Tar Products Works before taking active service, now demobilised, CHEMICAL NEWS Office, 16, Newcastle Street, Farringdon Street, desires Employment in London or the Provinces.- Address, T. T, London, E.C. 4. hemist required at once for Analysis of Ch Chrome Steel and General Metallurgical products. State experience and salary.-Address, C. S., CHEMICAL NEWS Office, 16, Newcastle Street, Farringdon Street, London, E.C. 4. phide with soda and hydrogen peroxide and adding Junior Assistant Chemist wanted for the Ful alcohol, a precipitate of sodium antimonate is obtained after thirty-six hours' standing. From the weight of this precipitate the amount of antimony present can be deduced. In an alternative process the antimony is determined as tetroxide, Sb204. A given weight of the sulphide is heated over a water-bath with hydrochloric and nitric acids. The solution is evaporated to dryness, taken up with hydrochloric acid, diluted, and filtered. The precipitate consists of silica and calcium sulphate. The antimony is contained in the filtrate, which is decomposed by HCl, and oxidised to give Sb204.-Revue des Produits Chimiques, 1919, xxii., 199. Research Laboratory. One preferred with B Sc. Degree, but not absolutely essential. Should have good knowledge of Geology and Palæobota y. State particulars of training and experience, age, and salary required. -Address, F. R., CHEMICAL NEWS Office, 16, Newcastle Street, Farringdon Street, London, E.C. 4. Metallurgical and Research Chemist (Univer sity training and extensive Works experience) will soon be free organising abilities and Technical knowledge are desired, at home or to accept another Engagemeat as such, or any position of trust where abroad During war was Chemist in charge of large Engineering firm. In first place please address communications to "L.," CHEMICAL NEWS Office, 16, Newcastle Street, Farringdon Street, London. E.C.4 University man (Demobilised Officer), first class in Chemistry and Mathematics at London Inter.B.Sc., and excellent testimonial from his Professor, desires situation, either of Secretarial nature or in some capacity utilising above qualifications. -Address, U. M., CHEMICAL NEWS Office, 16, Newcastle Street, Farringdon Street, London, E.C. 4. Young man (31), with good knowledge of Chemistry and Engineering practice, desires Situation at living wage with Chemical Engineering firin, or Assistantship in Works Laboratory of progressive firm which appreciates intelligent and willing service.-Address, Sharpe, 7,,Toll Road, Kincardine on-Forth GENT for Chemical and Agricultural Pro Determination of Arsenic in Volatile Cacodylic Compounds. L. C. Maillard.- Cacodyl and its compounds readily combine with oxygen to give cacodylic acid, which is a very stable derivative in ordinary conditions. It is non-volatile, has no smell, and is not toxic. For the purposes of analysis the best oxidising agent to use is persulphuric acid, employed in the form of ammonium persulphate. To extract the arsenic from the cacodylic acid the latter is attacked with a mixture of nitric and sulphuric acids, the excess of nitric acid is driven off by heating, and the arsenic is precipitated in the diluted solution as sulphide, and weighed either as sulphide, or as arsenic acid, or as magnesium pyroarsenate. Even in the case of a long series of operations, when an accumulation of errors might be feared, the author has found by a control experiment that this method gives excellent results in determining arsenic in volatile substances of the cacodyl series, and it is possible that it may be applicable to the case of other organic compounds con- TO MANUFACTURERS OF MILK FOOD PRODUCTS. taining arsenic of more or less comparable composition.Bull. Soc. Chim. de France, 1919, xxv.-xxvi., 192. Wednesday, June 11. ducts, well connected amongst important importation firms of Bordeaux and South-West of France for SULPHATE OF COPPER, requires Agency for Bordeaux. Highest references.-Write to Box 8059, Agence Havas, 105, Cheapside, London, E.C. 2. FORMULE, Chemical Processes for all kinds cas of products are wanted by French manufacturers; payment or on royalty basis -Write immediately offers to M. HENRI RAVEAU, 44, Rue de Dunkerque, Paris. 5000 gallons or more of FRESH WHOLE MILK or SEPARATED MILK For Sale daily at Creameries situate in Staffordshire, Derbyshire, and Leicestershire, together with use of se arate premises, including Boiler and Steam Power and Casein Drying Plant if required.-Apply to F. C. EDWARDS, Edwards' Creameries, Ltd., Granby Street, Hamps ead Road, London, N.W. SOUTH AFRICA and PATENT MEDICINES. South Africa is an enormous market for Conjoint Board of Scientific Societies, 5. (At Royal sold annually. Advertiser (Englishman, aged 45), who has very valuSociety, Burlington House). PATENT MEDICINES, some millions in value sterling being able business connection amongst Chemists, Merchants, and Dealers throughout South Africa, desires to REPRESENT Manufacturing Chemists who make Patent Medicines, and who are prepared to invest capital for Advertising, &c.-Please write "Zeal," care of Chas. Barker and Sons, White Lion Court, Cornhill, E.C. 3. If in good condition, Sixpence per copy will be paid for any of the undermentioned numbers of the CHEMICAL NEWS which may be forwarded to this office : 3052, December 6th, 1918. 3068, January 31st, 1919. 3069, February 7th, 1919. 16, NEWCASTLE STREET, FARRINGDON STREET, LONDON, E.C. 4 JOURNAL OF PHYSICAL SCIENCE James H. Gardiner, F.C.S. Established (WITH WHICH IS INCORPORATED THE "CHEMICAL GAZETTE "). in the Year 1859. Published Weekly. Annual Subscription, free by post 1. Entered at the New York Post Office as Second Class Mail Matter. Transmissible through the Post-United Kingdom, at Newspaper rate; Canada and Newfoundland, at Magazine rate. Registered as PRICE 4d. a Newspaper. POST FREE 4jd. J. and A. CHURCHILL. WILEY'S WORKS ON FOODS AND DRINKS. By FOODS and THEIR ADULTERATION. By HARVEY SECOND EDITION. With 63 Illustrations and many Tabl s. OSTWALD ON COLLOID CHEMISTRY. The Recognition o' Colloids, Theory of Colloids, and their Translated into English by Dr. MARTIN FISCHER, Professor of With 207 Diagrams. 21s. net, postage 6d. CHEMICAL COMBINATION AMONG METALS. The ANALYST'S LABORATORY COMPANION. By BRICKS and ARTIFICIAL STONES of NON-PLASTIC A MANUAL for MASONS. By J. A. VAN DER Kloes, By ARTHUR MARSHALL, A.C.G I., F I.C., London: 7, Great Marlborough Street, W. 1. CHEMICAL APPARATUS Pure Chemicals for Research Work JOHN J. GRIFFIN & SONS, LTD., KINGSWAY, LONDON, W.C June 13, 1919 Public Analyst in the Provinces, with varied Practice, has vacancy for an experienced Assistant. State age, experience, and salary required.-Address, P. A., CHEMICAL NEWS Office, 16, Newcastle Street, Farringdon Street, London, E.C. 4. The services of a Woman with a knowledge of Chemistry, German, and French are desired. State salary. -Address, Brown, CHEMICAL NEWS Office, 16, Newcastle Street, Farringdon Street, London, E.C. 4. Young man (31), with good knowledge of Chemistry and Engineering practice, desires Situation at living wage with Chemical Engineering firm, or Assistantship in Works Laboratory of progressive firm which appreciates intelligent and willing service.-Address, Sharpe, 7, Toll Road, Kincardine on-Forth. A GENT for Chemical and Agricultural Products, well connected amongst important importation firms of Bordeaux and South-West of France for SULPHATE OF COPPER, requires Agency for Bordeaux. Highest references.-Write to Box 8059, Agence Havas, 105, Cheapside, London, E.C. 2. FORMULE, Chemical Processes for all kinds of products are wanted by French manufacturers; payment, cash or on royalty basis.-Write immediately offers to M. HENRI RAVEAU, 44, Rue de Dunkerque, Paris. STAFFORDSHIRE EDUCATION COMMITTEE BRIERLEY HILL HIGHER EDUCATION COMMITTEE Applications are invited for the Post of HEAD MASTER of the Technical School, Brierley Hill, South Staffordshire. Experience in Teaching and acquaintance with the Iron and Steel Trades, or with the Chemistry of Refractory Materials, desirable. Initial salary £300 a year. Further particulars and forms of application may be obtained from the undersigned. Applications must be received not later than JusE GRAHAM BALFOUR, Director of Education. 30, 1919. County Education Offices, Stafford, June, 1919. 277 been shown by Walden (Ber., 1905, xxxviii.. 371) that cinnamic aldehyde has a very marked effect upon the rotation of ethyl tartrate and of methyl malate, the mere numerical values being greater than those recorded for either of these active substances in any other solvent, on which account we were anxious to ascertain whether the behaviour in the former case fitted in with the views previously developed or not. A solution of ethyl tartrate in cinnamic aldehyde, 9.64 (p=grms. active substance per 100 grms. of solu tion), was therefore prepared, and the rotation examined: for six colours of light. Three of these, yellow, green, and violet, were obtained direct from a mercury arc lamp, whilst the other three, dark red (vi), red (r2), and blue, which correspond to three fainter lines in the mercury arc, were obtained from a Nernst lamp by a method which has been described elsewhere (Fourn. Chem. Soc., 1916, cix., 1144). The wave-lengths of the light used were as follows ¿— ethyl tartrate could be examined for different colours of light over a sufficiently wide range of temperature, the graphs would have the appearance shown in Fig. 1; they have been traced up to the present from about the region a to the region ". In the paper now submitted an attempt has been made to follow the trend of these T-R curves towards low temperatures, adopting the same method as before. In the following experiments a start has been made in this direction, but before passing on to our primary purpose we thought it worth while to investigate one rather striking instance of solvent effect connected with the high temperature end of the diagram. It has Abridgment of a paper in the Proceedings of the Royal Society of Edinburgh, 1318-19, xxxíx., 18—34. y g b 67163 62343 5790 3 5460 7 4959 7 4358 3 It will be noticed that the rotations at low temperatures are great, and that as the temperature rises the rotation T-R curves for this solution are shown in Fig. 2, and are diminishes, which was in accordance with expectation. The there contrasted with those for ethyl tartrate in quinoline 13.601 (Fourn. Chem. Soc., 1916, cix., 1145, 1151). The curves are, on the whole, similar, but those for the cinnamic aldehyde solution lie higher on the diagram than those for the quinoline solution. In quinoline a minimum is apparent, but in cinnamic aldehyde the curves are only tending towards a minimum, which would lie at a distinctly higher temperature than could, meantime, be reached. Now |