The apparatus to be tested should be sent securely packed to the Director, the National Physical Laboratory, Bushy House, Teddington. The carriage to and fro must be paid by the sender. A letter of advice, which should contain the maker's name, a description of the instruments sent, and full directions for their return, must accompany all instruments sent for verification. The Laboratory Authorities insure against damage from fire, theft, or accident, apparatus while in their custody. They also insure against risks of transit to and from the Laboratory, apparatus sent to them for testing. They will not, however, be responsible for a sum exceeding £100 on any one instrument unless a letter has been received and acknowledged by them before the instrument is sent, advising that the instrument is being sent, and requesting them to insure it for some definite sum. The value for which goods are insured is the cost price of manufacture. In all cases, a sum sufficient to cover the cost of insurance will be charged with the fees. General Conditions. ALL analysts of food products, or feeding-stuffs, are familiar with the difficulty which is often experienced in filtering off the acid and the alkaline liquids in the determinations of crude fibre by the official method of the Association of Official Agricultural Chemists. Hence I wish to suggest the following modification of the usual procedure, which I have found to give very satisfactory results : Select a funnel of sufficient size to contain the entire bulk of the mixture to be filtered, and fit into its point a small platinum filtering cone. Introduce enough ignited asbestos-wool to fill the cone a little more than full. Upon moistening, the wool softens into a fluffy mass, which may be drawn down into a firm, close filter by suction. The Vessels to be tested should be marked permanently mixture to be filtered is now poured into the funnel, with with : the usual care to avoid disturbing the asbestos layer, and suction is applied. The filtrate obtained in this manner fibre. Filtration is very rapid in all cases except when has always been found to be free of suspended particles of *Proceedings of the Nineteenth Annual Convention of the Association of Official Agricultural Chemists, held at Washington, D.Ç. Chemical Notices from Foreign Sources. CHEMICAL NEWS, Aug. 28, 190s. working with finely ground flour or spices, which tend to clog the filter and impede the flow of the filtrate. In such cases place the funnel in an ordinary jacket of boiling water or steam in order to secure hot filtration, transfer the entire mass to be filtered to the funnel, and apply the suction as usual. Filtration will then proceed at the desired temperature and without further attention from the operator, thus avoiding the two objections to the use of the Gooch filter as recommended in the official method. After filtration and washing are complete, transfer the contents of the funnel to a platinum evaporating dish, rinsing the last particles of fibre from the funnel to the dish with a fine jet of distilled water. Evaporate off the water thus used, dry to constant weight, and complete the determination as usual. I prefer this mode of operation to the use of a paper filter, with correction for loss of weight sustained by the paper in a blank determination, as suggested by Winton ("Conn. Agr. Expt. Sta. Report," 1898, p. 189; and Bull. 65, Bur. of Chem., U.S. Dept. Agri., pp. 58, 154, and 155), for the reason that, in addition to the possibility of ob taining additional fibre from the paper used in the acid filtration, I have found that duplicate determinations of the correction to be applied do not always give concordant results, probably because of variations in the weight and composition of individual filters in any given pack of them. I have used the method outlined above for several years and upon a great variety of samples with uniformly satisfactory results. In the cases where filtration is slow it proceeds without attention from the analyst, thereby relieving the tediousness of the operation very materially. 107 efficient of re-combination, a, is proportional to the pressure. Catalytic Actions of Metals.-A. Trillat.-The author investigates the catalytic action of copper and platinum with regard to oxidation, dehydrogenation, condensation, and saponification, and finds, in all cases, that the catalytic action of metals is very complex. Ferrisulphuric Acid and Ethyl Ferrisulphate. A. Recoura. The author shows that ferrisulphuric acid behaves as a bibasic acid, analogous to chromosulphuric acid. He prepares ethyl ferrisulphate, and also studies the action of heat on ferrisulphuric acid. Prussian Blue and Turnbull's Blue. A New Class of Complex Cyanides.-P. Chrétien.-Neither Prussian nor Turnbull's blue are either ferrocyanides or ferricyanides. Soluble Prussian blue has a composition FeCу6FeK or Fe2Cy6K, whilst insoluble Prussian blue, which is prepared in the presence of an excess of a ferric salt, has the composition Fe-Cy18, 13H2O. Turnbull's blue has formula FesCy12,8H20 or (Fe2Cу6)2Fe,8H2O, and is the ferrous salt corresponding to the soluble blue. The author makes a thermometric study of these substances and the cyanide complex which they contain. Spartein: General Characteristics; Action of certain Reducing Agents.-Ch. Moureu and A. Valeur.Spartein is a liquid volatile alkaloid which has been employed in therapeutics for the past twenty years, under the form of sulphate, in the treatment of cardiac ailments. The authors investigate the physical constants of this substance, and give certain general indications as to its chemical nature. Its great stability with regard to reducing agents lead to the conclusion that the base is saturated, CHEMICAL NOTICES FROM FOREIGN and that all the liaisons between the atoms are simple SOURCES. NOTE. All degrees of temperature are Centigrade unless otherwise expresscd. Comptes Rendus Hebdomadaires des Séances, de l'Académie ́des Sciences. Vol. cxxxvii., No. 3, July 20, 1903. Estimation of Traces of Arsenic.-Armand Gautier. The new method of estimation of traces of arsenic which the author employs is of extreme simplicity, and can be used to detect minute traces of arsenic in animal organisms. The method is founded on the principle that when arsenic exists, even in very small proportion, in conjunction with iron in a mineral or potable water, the iron, when oxidised or precipitated, retains all this arsenic. The salt used is a polyferric sub-salt, and the extraction of the arsenic is so complete in this case that, under the experimental conditions which the author employs, 1/1000th of a m.grm. of arsenic, added either in the form of arsenite or arsenate to a litre of pure water is entirely removed by the iron and can be absolutely estimated, Curves of Sublimation.-A. Bouzat.-The author showed, in a previous research, that the curves of dissociation of the group sol. sol. + gas are deduced one from the other by a very simple law. The proportion of the absolute temperatures corresponding to the same pressure in any two systems whatsoever of the group remain constant for that pressure. The vaporisation and sublimation can be deduced from the dissociation. Law of the Re-combination of Ions.-P. Langevin. -When gases are rendered conductors of electricity, they justify in all their properties the hypothesis that the charges are carried by an infinite number of electric centres or ions --some being positive, some negative, all having the same charge in absolute value as that which transports a monovalent atom in electrolysis. The author finds that recombination takes place when, in the relative movements of the particles, the centres of two ions at the moment of perihelion are at a distance from one another less than a constant distance, o. The author also finds that the co ones. After a single investigation of the crude formula, little doubt remains that the molecule contains two, and perhaps three, closed chains. Isonitrosomalonic Ethers and their Transformation into Mesoxalic Ethers.-L. Bouveault and A. Wahl.V. Meyer and A. Müller have shown synthetically that nitrosomalonic acid is in reality an isonitroso-derivative identical with the oxime of meso-oxalic acid. It follows from CO2R, this that the isonitrosomalonic ethers, NOH=CCO2R' constitute the oximes of the corresponding meso-oxalates, CO2R COCO2R These latter bodies being difficult of preparation, the authors obtain them by saponification of their oximes and investigate their properties. He Action of Ammonia on Ethylene Oxide of B-cCyclohexanediol.-Léon Brunel.-In a previous paper the author describes the preparation of certain addition products of ethylene oxide of B-o-cyclohexanediol. now investigates the compounds obtained by the action of NH3 on this ether, and obtains the following compounds :Orthoaminocyclohexanol, OH C6H10-NH2; and, by reducing the proportion of ammonia, obtains two isomeric dioxycyclohexylamines, OH-C6H10-NH-C6H10—OH. No. 4, July 27, 1903. Preparation and Properties of Ruthenium Silicide.— Henri Moissan and Wilhem Manchot.-At the temperature of fusion of ruthenium this metal easily combines with silicon to give a silicide of formula RuSi, of density 5'40, perfectly crystalline, of great hardness, and very stable in presence of a large number of reagents. Arsenic in Sea-water, Table Salt, Mineral Waters, &c.; its Estimation in certain ordinary Reagents.Armand Gautier.-It has been known for some time that sea-water contains a small proportion of arsenic. The author estimates, by his method described in a recent paper, the arsenic in the water 30 km. from the coast of Brittany under the three forms-mineral, organic, and organised. Similar estimations are made on the arsenic in mineral waters and in the principal reagents used for the detection of this substance in physiology. A Combination of two Bodies which on raising the Temperature Unite, and which Separate below - 79 · -D. Grenez.-Acetone forms with mercuric iodide a solid orange-yellow combination, which is produced by the elevation of temperature a little above -94.9°, but which is only stable up to the temperature of -79°, at which temperature it is completely destroyed. Simultaneous Separation and Estimation of Baryta, Strontia, and Lime.-Lucien Robin.-The author describes a simple method for the separation and estimation of the three metals of the alkaline earths simultaneously when present in acid solution. The liquid is first rendered alkaline by ammonia, acidified with acetic acid, boiled, and potassium bichromate added in excess. The baryta is separated as chromate. The strontia is next separated by rendering the filtrate ammoniacal, boiling it, and introducing pure ammonium sulphate. The strontia is weighed as sulphate. Condensation of Acetylenic Ethers with Alcohol.Ch. Moureu.-Methyl phenylpropiolate, under the action Bristol meeting of the British Pharmaceutical Conference he was appointed one of the Honorary General Secretaries to fill the vacancy caused by the retirement of Mr. F. Ransom. UNIVERSITY COLLEGE, BRISTOL. CHEMICAL DEPARTMENT. The SESSION 1903-4 begins on October 6th. Lectures on Inorganic, Organic, and Advanced Chemistry will be delivered during the Session. The Laboratories are fitted with the most recent improvements for the study of Practical Chemistry and Metallurgy in all its branches. In the Evening the Laboratory is opened and Lectures on Inorganic Chemistry, at reduced fees, are delivered. Several Scholar. ships are tenable at the College. CALENDAR, containing full information, price 18. (by post, 18.4d.). JAMES RAFTER, Registrar and Secretary. of sodium methylate, can fix 2 or 1 mols. of methylic THE GLASGOW AND WEST OF SCOTLAND alcohol by the total or partial saturation of the acetylenic function. The new compounds thus formed correspond to benzoylacetic and cinnamic acids. The yield is usually about four-fifths of the theoretical yield. Constitution of Allyl Cyanide.-R. Lespieau.-Allyl cyanide is prepared by the action of potassium cyanide in the cold on allyl bromide, and as a result of the author's researches on this substance he believes it to correspond to the formula CH2=CH-CH2CN. Quinone-diketones. - Echsner de Coninck. The author's researches lead him to believe that the molecule of the quinone-diketones, quinone-phenols, &c., at a given temperature, and under the influence of H2SO4, rupture between the group CO and the substituted or non-substituted benzenic group. Afterwards these latter groups are decomposed and act on sulphuric acid, which is energetically reduced. By this means the rapid and abundant evolution of SO2, which the author observes in all his experiments, is explained. Alizarine and purpurine are less resisting than anthraquinone. Albumenoid matter in Maize Seed.-MM. Donard TECHNICAL COLLEGE. SESSION begins Monday, SEPTEMBER 21st, 1903. in the following Departments:-CIVIL, MECHANICAL, The LABORATORIES in the DEPARTMENTS of PHYSICS, CHEMISTRY, METALLURGY, MECHANICAL, and ElecTRICAL ENGINEERING, are equipped with the most approved apparatus. The Preliminary Examination for Candidates for the Diploma begins on September 14th. Names of intending Candidates must be lodged not later than September 11th. The CALENDAR (price, by post, 18. 4d.) and PROSPECTUS (gratis) will be sent on application to the SECRETARY, 38, Bath Street, Glasgow. and Labbé.—The authors continue their research on the REDRUTH SCHOOL OF MINES, CORNWALL. special properties of maisine, the albumenoid matter extracted from maize by means of boiling amylic alcohol. MISCELLANEOUS. Session 1903-1904 begins September 9th. A "Mining Certificate" is awarded to Students passing successfully through the School Course. PRACTICAL MINING CLASSES, under the Instruction Capt. W. HAMBLY (late Government Inspector, South Africa). Distinctions in Mine Surveying, in open Examination, our years in succession. SYLLABUS and every information on application to THE REGISTRAR. PATENTS FOR SALE. Absolutely necessary for CHEMICAL WORKS. Appointment.-Messrs. Howards and Sons inform us that they have entrusted to Mr. Edward White, B.Sc., F.I.C., the management of that branch of their business dealing with the manufacture of fine chemicals, and carried on under the style of Messrs. Hopkin and Williams, at Cross Street, Hatton Garden, E.C., which until recently was under the management of the late H. C. Everson, F.I.C. Messrs. Hopkin and Williams have a newly-built and equipped factory at Ilford, where the laboratories afford ample scope for research work in chemical technology and extension of business under Mr. White's direction. Mr. White, who is a Bachelor of Science of London University, and a Fellow of the Institute of Chemistry, was formerly Bell Scholar in the Pharmaceutical Society's School, acting afterwards as Demonstrator in the chemical laboratories at Bloomsbury Square. For the last fourteen years SILICATES OF SODA AND POTASH. he has been in charge of the Pharmaceutical Department IN THE STATE OF SOLUBLE GLASS OR IN CONCENTRATED SOLUTION. at St. Thomas's Hospital, where he has carried out original work dealing with pharmaceutical chemistry, one of the latest contributions from his laboratory being the solution OLDEST AND MOST RELIABLE MAKE. of the time-honoured kino gelatinisation problem. White is also well known as joint-author of "Pharmacopedia," and as the compiler of the last edition of the "St. Thomas's Hospital Pharmacopoeia." At the recent Mr. BLANK & ANDERS, Chemnitz, Germany. FULL STRENGTH GUARANTEED. Supplied on best terms by CHEMICAL NEWS; Advertisements. IMPORTANT TO ANALYSTS ARSENIC. Write at once for Circular fully illustrating and describing APPARATUS for determining the presence of Arsenic in THE INGREDIENTS OF BEER, and the Materials used in their Preparation, as used in the NEW GOVERNMENT LABORATORY. F.E.BECKER & CO. (WEI GEORGE 179 33-37 HATTON WALL, LONDON. Can be obtained from all businesses which deal in Chemical Apparatus. JAMES WOOLLEY, SONS & CO., LTD Chemical, Physical, and Photographic Apparatus, VICTORIA BRIDGE, FACTORY- Near STOCKPORT. GOLD MEDAL, PARIS, 1900. CHARLES LOWE & CO. (ESTABLISHED 1860). PURE CARBOLIC ACID, Cryst. at 42°2 C. Discovered MEDICINAL' do. do. Hydrate of Cryst. at 35° C. 35° 29° 12° C. do. No. 3 do. No. 4 CARBOLIC ACID DISINFECTING POWDER. CARBOLIC TOWN OFFICES 43, Piccadilly, MANCHESTER. GOLD MEDAL, PARIS, 1878. ACID GLYCERINE ACETONE. SOLUTIONS. WARDLE'S FERRICUM (Sewage Precipitant). (Cryst. PICRIC ACID and Paste). AURINE (Rosolic Acid), Cake and Solution. London: Printed and Published for the Proprietor by EDWIN JOHN DAVEY, at the Office, 16, Newcastle Street, Farringdon Street, E.C. August 28, 1903. |