On May 6 and 13, Sir William Bragg will deliver two lectures on "The Imperfect Crystallisation of Common Things "; on May 20 and 27, Mr. U. R. Evans will deliver two lectures on 66 Corrosion, Tarnishing and Tinting of Metals," and on June 3 and 10 Dr. J. Newton Friend will deliver two lectures on (I) "Iron in Antiquity" (II)" Science in Antiquity.' On Saturdays, at three o'clock, Dr. W. T. Calman will give two lectures on "The Shipworm," beginning on April 17; to be followed by two by Dr. Percy C. Buck on "The Song Form in England," with musical illustrations, May 1 and May 8; two by Dr. G. C. Simpson on Atmospheric Electricity," May 5 and May 22; and one by Professeur Alexandre Moret on "Une Revolution sociale en Egypt. vers 2,000 Av. J-C. (in French), May 29. The Friday Evening Discourses will be resumed on April 16, when Dr. A .W. Hill will deliver a discourse on "The Quest for Economic Plants." Succeeding discourses will probably be given by Prof. R. Whiddington, Dr. W. H. Eccles, Sir Frederick Kenyon, Mr. Seton Gordon, Sir Almroth Wright, Prof. J. Garstang, Prof. J. C. M’Lennan, of Toronto, and other gentlemen. 66 Sir S. H. Wilson, K.C.M.G., K.B.E., C.B., Permanent Under-Secretary of State for the Colonies, will preside. Wednesday, May 5, at 8 p.m. (Ordinary Meeting.) C. F. Elwell, B.A., "Radio-Its Past, Present and Future." Professor William Henry Eccles, D.Sc., F.R.S., will preside. Thursday, May 6, at 4.30 p.m. (Special Meeting.) Sir Frank Baines, C.V.O., C.B.E., "Preservation of Ancient Cottages." Sir Charles C. Wakefield, Bt., C.B.E., LL.D., will preside. Friday, May 7, at 4.30 p.m. The Rt. Hon. Lord Hardinge of Penshurst, will preside. (Indian Meeting.) Herbert Baker, A.R.A., F.R.I.B.A., "The New Delhi. SOCIETY OF PUBLIC ANALYSTS AND OTHER ANALYTICAL CHEMISTS. The next Meeting of the Society will be held on Wednesday, May 5, at the Chemical Society's Rooms, Burlington House, Piccadilly, W.1., at 8 p.m. The following papers will be read : 66 The Detection and Determination of Glycerin in Tobacco." By A. Chaston Chapman,F.R.S., F.I.C. "Further Notes on the Crystalline Bromides of Linseed and other Oils." By Harold Toms, M.Sc. (Work done under the Analytical Investigation Scheme.) of "The Polarimetric Determination Sucrose in Condensed Milk." By A. Bakke and P. Henegger. (Summarised by E. B. Hughes, M.Sc., F.I.C.). "The Determination of Very Small Quantities of Iron." By Henry L. Smith, B.Sc., F.I.C., and J. H. Cooke, B.A., A.I.C. "The Separation of Iridium from Iron." By W. R. Schoeller, Ph.D. "The Determination of Total Alkaloids, Sugar and Oily Substances in Opium." By Jitendra Nath Rakshit. lege of Science, Imperial Institute Road, South Kensington, S.W.7., on Tuesday, May 11, at 5.30 p.m., and the Chair will be taken by Sir William Bragg, President of the Institute. THE INSTITUTE OF METALS. The sixteenth annual May lecture of the Institute of Metals will be delivered by Professor H. C. H. Carpenter, F.R.S., on "Single Metallic Crystals and Their Properties," at a General Meeting of the Institute, to be held at the Institution of Mechanical Engineers, Storey's Gate, Westminster, London, S.W.1., on Wednesday, May 19, 1926, at 8 p.m. Non-members of the Institute desirous of attending the May lecture should apply to the Secretary, Mr. G. Shaw Scott, M.Sc., 36, Victoria Street, London, S.W.1. THE INSTITUTION OF ELECTRICAL ENGINEERS. Savoy Place, Victoria Embankment, W.C.2. Wireless Section Meeting.-Wednesday, May 5, at 6 p.m. (Light refreshments at 5.30 p.m.) 66 On the Cause and Elimination of Night Errors in Radio Direction Finding." By Dr. R. L. Smith-Rose, M.Sc., and R. H. Barfield, M.Sc. New Patents. These particulars of New Patents of interest to Readers have been selected from the Official Journal of Patents, and are published by special permission of the Controller of His Majesty's Stationery Office. Latest Patent Applications. 9,203.-American Smelting & Refining Co. Recovery of zinc as sulphate from dross. April 7th. 9,204.-American Smelting & Refining Co.-Recovering metals. April 7th. 9,529.-Lacell, H. G.-Production of chlorides from metallic oxides, etc. April 10th. 9,536. New Jersey Zinc Co.-Treatment of zinciferous materials. April 10th. 9,172. Soc. Anon. des Fours à Coke Semet-Solvay et Piette.-Production of ammonium sulphate. April 7th. Specifications Published. 241,547.-Metropolitan Vickers Electrical Co., Ltd.-Devices for the chemical treatment of gases. 247,523.-Farbenfabriken vorm. F. Bayer & Co.-Process for the manufacture of alkali hydrosulphites. Printed Copies of the full Published Specification may be obtained from the Patent Office, 25,Southampton Buildings, London, W.C.2., at the uniform price of 1s. each. Abstract Published. 247,471.-Desulphurising iron ores.-Millar, W. S., 183, Fox Lane, Palmers Green, London. Iron oxide; sulphur.-The process for desulphurisating iron ores by means of sulphur dioxide described in the parent Specification is carried out by the use of gases containing at least 50 per cent. of sulphur dioxide. Burner gases enriched with sulphur dioxide or the pure gas itself may be used. The iron remains in the furnace as a porous highly magnetic oxide and sulphur is condensed from the issuing gases. The introduction of steam facilitates the process. MICA BRARY The Commissioners of His Majesty's Works, etc., are prepared to receive Tenders before 11 a.m., on WEDNESDAY, 9th MAY, 1926, for the supply of SODA CRYSTALS, &c. Forms for Tender, etc., may be obtained n application to the Controller of Suplies, I.M. Office of Works, etc., King Charles treet, Westminster, London, S.W.1. THE NIVOC VACUUM SUBLIMER For use in the examination, extraction and purification of organic and inorganic compounds. Designed by T. J. HEDLEY, A. M.I.Chem.E., Department of Chemistry, University of Birmingham. Consists of a massive brass temperature equaliser with gas burner and a water cooled jacket. A boiling tube with a close fitting internal sleeve lies within the cooling jacket the lower end resting in the temperature equaliser. The compound is introduced into the boiling tube and closed with a rubber bung through which a glass tube passes connecting to the vacuum pump. When the necessary temperature is reached the compound will sublime into the interior of the sleeve which may be withdrawn with the sublimate intact. Full particulars from: F. E. BECKER & Co., W. & J. GEORGE (LONDON), LTD., PROPRIETORS. 17-29, HATTON WALL, LONDON, E.C.1. Sanitäts Porzellan-Manufaktur-W. HALDENWANGER, SPANDAU, GERMANY. Representative: E. O. Maempel, Finsbury Pavement House, Moorgate Street, London, E.C.2. BERLIN-PORCELAIN-HALDENWANGER Can be obtained from all businesses which deal in Chemical Apparatus. GRAMMAR OF LOGIC. Th 100 Questions and Answers on Grammar of Logic or How to Reason Co rectly, by J. E Roscoe, M.A., Oxon. An invaluable book for all who desire excel as speakers and who wish to reas convincingly. MERTON HOUSE, SALISBURY SQUAR LONDON, E.C.4. ( tions : = Cu + H2SO1 CuO + H2O + SO, CuO + H,SO = CuSO, +HO After considerable experimentation in which the test was performed under many varied conditions, the following procedure was found to give the most sensitive test. Procedure I.-Dissolve the substance in a test-tube with 1 cc. of water. Add to this solution one-half gram of fine copper punchings which should be clean and bright. (Note 1.) Add 1 cc. of pure conc. H,SO (Note 2), heat the solution to boiling and boil slowly (Note 3) for one minute. The above procedure was applied to soluamounts of tions containing varying nitrates. The results obtained are given in Table I. TABLE I. PROCEDURE I. No. NaNO,. Color of Solution. NO, as Gas given off. Pale blue NO2 |