Only a Few Tubes left. ARMBRECHT, NELSON & CO., 71 & 73 DUKE STREET, GROSVENOR SQUARE, W. Telephone. GERRARD, 4942. THE SYTAM SYSTEM Saves an incredible amount of wall space and completely utilises dark corners, recesses, and out-of-the-way places. Prevents crowding and confusion. Allows for extension as and when required. Always room for more, hence reorganisation seldom or never necessary. Saves time, lightens work, and increases comfort by producing perfect order in the Laboratory, Library, Study, Home, Office, &c. SOME SYTAM FITTINGS. 1. THE BOTTLE ELEMENT. One hundred 4 oz bottles are arranged in one Sytam Bottle Element occupying less than 1 sq. ft. of wall space, each bottle is instantly located, removed or replaced, and any size from -oz. to a Winchester can be accommodated in one and the same element. 2. THE CLOSED-FRONT BOOK ELEMENT. 3. THE OPEN-FRONT BOOK ELEMENT. THE AUTHOR'S FILE. 4. For division of subject into headings, chapters or sections. 18-inch Apps-Newton Coil for sale, in perfect 5. THE TWIN DESK TRAYS. condition. No trace of oxidation on the vulcanite. G. BowRON, 57 Edgware Road, W. Metallurgical Laboratory, well equipped for experimental work, to let at low rent. One minute from Station. Fifteen minutes to City. Apply MARSHALL & Co., Campbell Works, Stoke Newington, N. (close to Station, G. E.R.). Tel., 79 Dalston. 6. THE PAMPHLET FILE. THE SYTAM FITTINGS CO., 18 & 19 BASINGHALL BUILDINGS, LEEDS. Apparatus for estimation of sulphur in se oxide NEW DOUBLE COX'S IMPROVED SURFACE CONDENSER. HIGH FREQUENCY APPARATUS THE "IDEAL." This is the best and cheapest Condenser on the market; all delicate parts are protected by outer jacket, and the water cannot overflow into the distillate. Made in two sizes, 6" and 8", 4/6 and 5/6 each. NATURE says:-" This is one of the most compact and efficient condensers which has come before our notice. We have tested it for condensing such volatile substances as ether, carbon disulphide, and acetone, and have found that even with rapid distillation the condensation is very complete. Generally speaking, in order to condense these substances satisfactorily, it is necessary to employ a very long condenser; of course, As this means using a great amount of bench space. the new condensers are used in a perpendicular posi. tion, the saving in space is very great." SOLE MAKERS BREWSTER, SMITH & CO., 6 CROSS STREET, FINSBURY PAVEMENT, LONDON, E.C. All kinds of Apparatus for Science Teaching. FREDK. JACKSON & Co. (Late MOTTERSHEAD & CO.), 14 CROSS STREET, MANCHESTER Goods Entrance: 10 Half-Moon Street. LABORATORY FURNISHERS, Importers, Manufacturers, and Dealers in Of every Description. AND EVERY LABORATORY REQUIREMENT. Illustrated Catalogue of Apparatus, with Price List of Chemicals, free on application. Telegraphic Address-"APPARATUS, MANCHESTER." Telephone Number-2238. SECOND-HAND TELESCOPES. 6 in. Dallmeyer Equatorial, Clock, complete, £100. 4 in. Alvan Clark, Equatorial by Cooke, £50. Several 3 in. Student Telescopes, by leading makers, £4 10s., £6 10s., £8 10s., £10. SECOND-HAND SPECTROSCOPES. Single, 2, and 3 Prism, by Browning, £4 10s., £8 10s., £10. SECOND-HAND MICROSCOPES. Watson's Edinburgh H., 3 powers and fittings, complete, as new, £16 10s. Swift Army Bacteria, complete, £15. Leitz 2b, with rack, substage, and fittings, £6 10s. MANY OTHERS, ALL KINDS. LISTS ON APPLICATION. A. CLARKSON & CO., 28 BARTLETT'S BUILDINGS, HOLBORN CIRCUS, LONDON. ALFRED E. DEAN, THE LARGEST MAKER IN ENGLAND of Apparatus in all Departments of ELECTRO-THERAPEUTICS including Radiography, High Frequency, Hydro-Electric and Light Baths, Finsen and other Light, Cautery, Electrolysis, &c. INDUCTION COILS AND STATIC MACHINES A SPECIALITY. CONTRACTOR TO THE WAR OFFICE, INDIA OFFICE, AND ADMIRALTY, BRITISH AND FOREIGN HOSPITALS, &c. LISTS ON APPLICATION. This apparatus, when working off a 10 in. Coil, will give from 800 to 1000 milli amperes. Price, as illustrated, L but with New Pattern Spark Gap and New Full particulars of above, and all other forms of ElectroTherapeutic Apparatus, are contained in our ILLUSTRATED CATALOGUE in X-RAYS, &c. (including Instructions to Beginners), post free. SCIENTIFIC AND EDUCATIONAL BOOKS NEW & SECOND HAND. LARGEST STOCK in LONDON of SECOND. Mathematical, Theological, and Foreign Books. KEYS AND TRANSLATIONS. 104 CHARING CROSS ROAD, LONDON, W.C. (Formerly of 39 HOLYWELL STREET, STRAND). ROYAL IRISH ACADEMY PROCEEDINGS. Volume XXV. Section B. No. 5. Sewed, 6d. ON THE GROWTH OF CRYSTALS IN THE CONTACT- WILLIAMS & NORGATE, 14 Henrietta Street, London, W.C. MEDICAL ELECTROLOGY AND RADIOLOGY, AN INTERNATIONAL MONTHLY REVIEW COVERING FOREIGN SCIENTIFIC BOOKS and Periodicals promptly supplied at lowest rates. CATALOGUES post free ON APPLICATION. 59 CASTLE STREET EAST, OXFORD STREET, LONDON, W. THOMAS PRINCE, SCIENTIFIC BOOKSELLER. All books advertised and reviewed in NATURE are supplied at lowest cash prices. Orders by post promptly dispatched. With 30 Original Illustrations. Price 2s. 6d. ▲ Guide to the Prevention and Control of Dental Diseases. By R. DENISON PEDLEY, L.D.S. Eng., F.R.C.S. Ed., Dental Surgeon to the Evelina Hospital, Southwark. REMAINDERS OF STANDARD WORKS ON NATURAL HISTORY, &c., at very low prices. ALL NEW AS PUBLISHED. Adams (Henry, F.L.S., and Arthur)-The Genera of Recent Mollusca, with 138 full-page plates, containing thousands of figures arranged by Sowerby, 3 thick vol., 8vo (pub. £4 10s.) 16s. 6d., postage rod. Browne (Montagu, F.G.S.)-Artistic and Scientific Taxidermy and Modelling, a Manual of Instruction in the Methods of Preserving Natural Objects, Modelling of Foliage, &c., 22 full-page engravings and 11 text illustrations, 8vo gilt extra (1 15.) A. & C. BLACK, 5S., postage 6d. Cooke (M. C.)-The British Fungi: A Plain and Easy Account of, coloured plates of 40 species, cr. 8vo (6.) 3s., postage 4d. Microscopic Fungi: An Introduction to the Study of Microscopic Fungi, Rust, Smut, Mildew, and Mould, 269 coloured figures, by J. E. Sowerby, cr. 8vo 16s.) 3s., postage 4d. Dallas (W. S.)-Elements of Entomology: An Outline of the Natural History and Classification of British Insects. Illustrated with 21 text engravings of Beetles, Grasshoppers, Butterflies, Moths, &c, post 8v (pub. 8s. 6d.) 1s. 6d., postage 4d. Dixon (Charles)-The Story of the Birds, the Origin and Salient Characteristics of Birds, their Groups, Distribution in Space, Means of Dispersal and Migrations, General Habits and Functions, Love Displays, Repro luction, Nest, and Eggs, cr. 8vo (pub. 5s.) GEORGE ALLEN, 1s. 9d., postage 4d. Emerson (P. H.)-Birds, Beasts, and Fishes of the Norfolk Broadland, 68 full-page and text illustrations, 8vo (pub 125 6d.)... NUTT, 4s. 6d., postage 5d. Greg (R. P., F.G.S.) and William LettsomManual of the Mineralogy of Great Britain and Ireland, illustrated, 8vo (pub. 155.) 1s. 6d., postage 5d. Jenyns (Leonard) — Observations in Natural History (being a companion work to White's "Selborne "'], with an in roduction on habits of observing as connected with the study of that science, also a Calendar of Periodic Phenomena in Natural History, post 8vo (pub 10s. 6d.) 3s.. postage 4. Jones (Professor T. Rymer, F.R.S.)-The Aquarium Naturalist, A Manual for the Seaside, containing about 100 coloured illustrations of interesting objects of the seashore, thick post 8vo (nearly 530 pages) (pub. 18s.) 3s., postage 4d. "The best of all the seaside books which have come under our notice." Rimmer (R.-The Land and Freshwater Shells of the British Isles, illustrated, 8vo (pub. 5s.) 2s., postage 4d. Smith (J., A.L.S.)-British and Foreign Ferns: Revised and greatly cr. 8vo (pub. 7s. 6d.). 2s., postage 4d. with a Treatise on their Cultivation. enlarged, with many illustrations, 450 pp., Taylor (J. E.)-Flowers: Their Origin, Shapes, Perfumes, and Colours, 32 coloured figures, and 161 woodcuts, cr. 8vo (pub. 75. бd.) 2s. 6d., postage 4d. -The Aquarium: Its Inhabitants, Structure, and Management, with 238 woodcuts, cr. 8vo (pub. 35. 6d.) 2s., postage 4d. Half-Hours at the Seaside, illustrated with 250 woodcuts, cr. 8vo (pub. 2s. 6d) 2s., postage 4d. -Half-Hours in the Green Lanes, illustrated with 300 woodcuts, cr. 8vo, gilt edges (pub. 2s. 6d.) 2s., postage 4d. Theobald (F. V.)-The Parasitic Diseases of Poultry [Animal and Vegetable, including Chapters on Protozoa, Insects, Mites and Worms, with List of Parasites upon Domestic Cocks and Hens, &c.], 23 illustrations, post 8vo (pub 2s. 6d) 1s. 6d., postage 3d. New Catalogue free on application, JOHN GRANT, Wholesale Bookseller, 31 GEORGE IV. BRIDGE, EDINBURGH. Complete in THREE VOLUMES, Half-Bound. Vol. I., with 236 Illustrations, 8vo, £2 2s. Vol. II., with 240 Illustrations, 8vo, £2 2s A DICTIONARY of APPLIED CHEMISTRY By T. E. THORPE, C.B., Ph.D., D.SC., Director of Government Laboratories, London. ASSISTED BY EMINENT CONTRIBUTORS. &C., WORKS by G. S. NEWTH, F.I.C., F.C.S., Demonstrator in the Royal College of Science, London; Assistant Examiner in Chemistry, Board of Education. A TEXT-BOOK OF INORGANIC CHEMISTRY. Tenth Edition. With 155 Illustrations. Crown 8vo. 6s. 6d. CHEMICAL ANALYSIS, QUANTITATIVE & QUALITATIVE. Fifth Edition. With 100 Illustrations. Crown 8vo. 6s. 6d. CHEMICAL LECTURE EXPERIMENTS. New Edition. With 230 Diagrams. Crown 8vo. 6s. ELEMENTARY PRACTICAL With 108 Illustrations and 254 Experiments. CHEMISTRY. Crown 8vo. 2s. 6d. LONGMANS, GREEN & CO., 39 PATERNOSTER ROW, LONDON, E.C. THE EXECUTORS OF THE LATE COLONEL WATKIN, C. B. (Inventor of the Range Finder) are offering the following for sale : I. 6 in. Holtzaffel Lathe, with divided headstock and overhead gear, H.P. de Dion engine, water cooled with tanks, &c., and dynamo 7-0 volt Accumulators in teak cases, 9 amps. II. 4 III. TO SCIENCE MASTERS, especially those taking ELECTRICITY as special subject. Wanted by July 1 next for important College, well-qualified Master for Electricity and who has had some experience in the organisation of the work of a local Technical Instruction Committee. Salary, £150 to £200 per annum. Candidates for the above and those seeking posts for the term commencing in September next should apply forthwith, giving details as to qualifications and enclosing copies of testimonials, to GRIFFITHS, SMITH, POWELL. & SMITH. School Agents (Estd. 1833), 34 Bedford Street, Strand, London. ROYAL SOCIETY OF LONDON. MACKINNON RESEARCH STUDENTSHIPS. There are two Studentships each of the value of £150. One of them is awarded for research in the group of the Physical Sciences, including Astronomy, Chemistry, Geology, Mineralogy and Physics. The other is awarded for research in the group of the Biological Sciences, including Anatomy, Botany, Palæontology, Pathology, Physiology and Zoology, The Studentships are awarded annually for one year, but are renew. Able for a second year. Under exceptional circumstances they may be renewed for a third year. The Studentships are restricted to British subjects. Further Applications must be received not later than June 5. particulars and forms of application can be obtained from the Assistant Secretary of the Royal Society, Burlington House, London, W. JUST PUBLISHED. TWENTY-SIX GRADUATED EXERCISES IN GRAPHIC STATICS, some in Two Colours, and with Skeleton Data to practise upon, and including the Application to Roofs, Moving Locomotives, Retaining Walls, Lévy's Steel Arches, Girders (Original Constructions), Masonry Arches, Lévy's Weight Tables, with an Essay on Graphical Statics, in the form of a Running Commentary on the Exercises, each of which has full Instructions printed on its face, the whole forming a Supplement to the Authors' Elementary Applied Mechanics. By T. ALEXANDER, M.Inst.C.E.I., Professor of Engineering, Trinity College, Dublin; and JUST PUBLISHED. JOURNAL OF THE ANTHROPO LOGICAL INSTITUTE. Vol. XXXIV. Part II. JULY-DECEMBER, 1904. Contents: Les Six Races composant la Population actuelle de l'Europe (the Huxley WITH MANY FULL-FAGE PLATES AND ILLUSTRATIONS IN THE TEXT. LONDON: THE ANTHROPOLOGICAL INSTITUTE, 3 HANOVER MARINE OBJECTS, Hydrozoa extended without pressure, sponge sections, &c. Apply for Lists. Dispersal of Mr. HORNELL'S collection. Flower and Leaf Buds, Stems, Roots, &c., new, from 3d. each. Lists. Exhibition Groups of Diatoms, &c, in symmetrical patterns. EDINBURGH H., by Watson, for sale, and others; several Objectives, Condensers, &c. PRISMATIC BINOCULARS, LANIERN SLIDES, Church Architecture, Swiss, Egypt and Holy Land views, all first class. Fine mounted collection of Grasses, Mosses, Ferns, Marine Algæ. Detailed List sent on application, as stock is always changing. Mr. HERBERT CLARKE, 104 LEADENHALL STREET, E.C. Tel.:-1316 CENTRAL. £1 1 0 15 O The Scintillations seen in this instrument are from Pure Radium Bromide of the Highest Known Activity, and are brighter and more plentiful than those produced from Pitchblende or other bodies of low radio-activity. A. C. COSSOR, 54 Farringdon Rd., London. RUBIDIUM, TANTALUM, GERMANIUM, in Gramme Tubes at Reasonable Prices. DRAWING INSTRUMENTS. Ask for Table of Rare Elements by E. L. N. ARMBRECHT, Best Make and Finish. SET SQUARES, T SQUARES, DRAWING BOARDS. Obtained through any Optician. ROBERT NICHOLL, 153 HIGH HOLBORN, LONDON. 71 & 73 DUKE STREET, GROSVENOR SQUARE, W. Telephone: GERRARD, 4942. JUST PUBLISHED. 290 pages, 8vo. cloth, price 4s. 6d. net. Important New Publication issued by the Chemical Society. ANNUAL REPORTS on the PROGRESS of CHEMISTRY for 1904. An epitome of the principal definite steps in advance which have been accomplished during the year 1904. GURNEY & JACKSON, 10 PATERNOSTER Row, LONDON, E. C. RECENT & COMING ECLIPSES. BY Sir NORMAN LOCKYER, K.C.B., F.R.S. Second Edition, containing an account of the Observations made at Viziadrug, in India, in 1898, and of the conditions of the Eclipses visible in 1900, 1901 and 1905. 8vo. 6s. net. MACMILLAN AND CO., LIMITED. LONDON. HARVEY PEAK (BY APPOINTMENT TO THE ROYAL INSTITUTION OF GREAT BRITAIN.) READING MICROSCOPES, RESISTANCE COILS, &c. . 56 CHARING CROSS ROAD, LONDON, W.C. SPECIAL TERMS TO COLLEGES, SCHOOLS, INSTITUTES, &c. |