MATHEMATICAL MASTER wanted for important Public School, one with Hons. Degree looked for. Salary, £140, resident. Many other vacancies for Mathematical and Science Masters. Apply giving full details and enclosing copies of testimonials, to GRIFFITHS, SMITH, POWELL & SMITH, Tutorial Agents, 34 Bedford Street, Strand, London. SCIENTIFIC INSTRUMENT TRADE. Advertiser, 30, ten years' experience with leading firms, desires partnership or post with view to same. Well educated; good qualifications. No. 2072, NATURE Office. WANTED: RADIUM.-Armbrecht, Nelson & Co., 71 and 73 Duke Street, Grosvenor Square, London, W. MOSQUITOES, GNATS and FLIES will not attack if a little of Ambrecht's Pyrethrum is put on the skin. It protects for about 12 hours, and also cures stings of any insects-wasps and bees included. Price 2s. 9d. post free U.K.; Germany, Holland and English Colonies 18., France and Italy 1s. 6d, extra.-Armbrecht, Nelson & Co., 71 and 73 Duke Street, Grosvenor Square, London, W. HIGHLY EDUCATED WOMEN ACCUSTOMED TO SCIEN. TIFIC MSS. (Classical Tripos, Intermediate Arts, Cambridge Higher Local) Modern Languages. Research, Revision, Translation, Shorthand. Dictation Room. The Cambridge Type-writing Agency, 10 Duke Street, Adelphi, W.C. SECOND-HAND BOOKS at Halt Prices!! New Books at 25 per cent. Discount! Books in all branches of SCIENCE, TECHNICS, MATHEMATICS, and NATURAL HISTORY, and for all Examinations (Elementary and Advanced). Sent on approval. Catalogues free. State wants Books bought; best prices viven.-W. & G. FOYLE, 135 Charing Cross Road, London. MUSEUM ATTACHMENT FOR BINOCULAR PRISMATIC FIELD GLASSES, by means of which they can be used at a distance of 1 metre from the object examined, which is thus seen at an actual magnification. Particulars on application to H. F. ANGUS & CO., 83 Wigmore St., London, W. PLATINUM Crucibles, Scrap, Utensils, Wire, Foil, Residues, &c., PURCHASED AT HIGHEST PRICES. THE LONDON REFINING & METALLURGICAL WORKS, 32 CLERKENWELL ROAD, LONDON, E.C. Assayers, Gold, Silver and Platinum Refiners & Dealers. Bankers: London City and Midland. Telephone: 388 Holborn. SUCCESSFUL INVENTORS HAVE THEIR IDEAS WORKED OUT AND MODELS MADE AT Wm. K-L. DICKSON'S Sale by Auction. TOWN HALL, LEEK. MONDAY, JULY 26, 1909. FERGYSON & SON, instructed by the Exors. of the late Sir Thomas Wardle, will sell as above, the costly modern MICROSCOPES with all Accessories, by Beck and other well-known makers, representing many hundreds of pounds in value. TELESCOPES, OPERA GLASSES, MAGIC LANTERNS, SILK PRODUCING MOTHS in CABINETS, BUTTERFLIES, GEOLOGICAL SPECIMENS, &c., also complete X-RAYS and APPARATUS. Business at 1 and 6 p.m. Catalogues with full details one week before Sale (free) from the Auction, Valuation, Estate, Insurance and Shipping Agency Offices, Ball Haye Road, Leek. 72% of Hg ▲ 5461 is transmitted by the New Wratten MERCURY GREEN LINE Seven times more efficient than any other Filter in existence. WRATTEN & WAINWRIGHT, Ltd., CROYDON. A NEW ROTARY HIGH VACUUM PUMP. All rotating portions are of Steel, and therefore CANNOT BREAK, The pump is of sound mechanical construction, suitable for factory or laboratory use, and gives the highest obtainable vacua with great rapidity. PRICE AND PARTICULARS ON APPLICATION. A. C. COSSOR, Ltd., 54 FARRINGDON ROAD, LONDON, E.C. F. E. BECKER & CO. (W. and J. George, Ltd., Successors), 159 and 160 Great Charles Street. PHILIP HARRIS & Co., Ltd., Edmund Street. STANDLEY BELCHER & MASON, Ltd., Church Street. Dublin. PHILIP HARRIS & Co., Ltd., 179 Great Brunswick Street. Leeds. 14 Commercial Street. Co.. Manchester. FREDK. JACKSON & 14 Cross Street. ORME & CO., Ltd., 17 Russell Street, London Road. JAMES WOOLLEY, SONS & Co., Ltd., Victoria Bridge. & 19 Newcastle-upon-Tyne. BRADY & MARTIN, Ltd. London. F. E. BECKER & CO. (W. and J. George, Ltd., Successors), 33 to 37 Hatton Wall, Hatton Garden, E.C. REYNOLDS & BRANSON, Ltd., A. GALLENKAMP & Co., Ltd., 19 & 20 Sun Street, Finsbury, E.C. And other leading Wholesale Houses. FREDK. JACKSON & CO., Ltd., 14 CROSS STREET, MANCHESTER. Goods Entrance: 10 Half-Moon Street. LABORATORY FURNISHERS. Importers, Manufacturers, and Dealers in CHEMICAL AND PHYSICAL APPARATUS Of every Description. THE "RICID" SERIES Fitted with the Improved Rigid Head Joint and Straight Bow OF DRAWING INSTRUMENTS. Full Catalogues sent Post Free on application. 61 OLD COMPTON ST., SOHO, LONDON, W. DENT'S ASTRONOMICAL CLOCKS, SIDEREAL OR MEAN TIME CLOCKS FOR OBSERVATORIES, £21 & UPWARDS. Nature says: "Should find its way into many observatories where an accurate instrument is required at a moderate cost. For the sum of £21 they supply a clock with a 10-inch dial, dead-beat escapement, and wooden rod seconds pendulum in a solid mahogany case and after examining the instrument we have no hesitation in pronouncing it a marvel of cheapness." E. DENT & CO., Ltd., Watch, Clock, and Chronometer Makers By Special Appointment to H.M. the King. Makers of the Great Westminster Clock, Big Ben. Makers of the Standard Clock of the Royal Observatory, Greenwich, and the Principal Observatories throughout the World. TELESCOPES NEW AND SECOND HAND. SECOND-HAND TELESCOPES ON STOCK. 23" Dollond, £8 10s.; 3" Wray, £12 10s.; 3" Cooke, £22 10s.; FINE CHEMICALS, VOLUMETRIC SOLUTIONS, 4" Cooke, £30; 3" Dollond (Student), £10; 3" Wray, £14; ARGAINS IN BOOKS, all new.-Harmsworth Atlas, 50s., for 255.; Debrett's Peerage, 1907. 2 vols., 335., for 6s. 6d.; Business Cyclopedia, 7 vols., 52s. 6d., for 30s.; Connold's British Vegetable Galls, 155., for 8s. 6d.; Indian Art at Delhi, 1904, 125. net, for 6s.; Crawley's Tree of Life, 125., for 6s. 6d. ; Harvie-Brown's Travels of a Naturalist in Northern Europe, 2 vols., 63s., for 10s. 6d.; Kappel and Kirby's British and European Butterflies, coloured plates. 255. net, for 12s. 6d.; Furnival's Leadless Decorative Tiles, Faience and Mosaic, 6 6s., for 21s.; Harmsworth's Encyclopædia, 56s., 10 vols., for 325.; Staffordshire Pots and Potters, 215., for 10s. 6d.; Cust's Authentic Portraits Mary Queen of Scots, 63s., for 18s. 6d.; A. R. Wallace's My Life, 2 vols., 255. net, for 8s. 6d.; Plunket's Ancient Calendars and Constellations, 9s., for 4s. 6d.; Scherren's Zoological Society of London, 30s., for 10s. 6d.; Johns' Flowers of the Field, coloured plates, 7s. 6d.; Round's Federal England, 12s. 6d., for 6s. 6d.-BAKER'S GREAT BOOKSHOPS, 14 and 16 John Bright Street, Birmingham. SCIENCE PROGRESS IN THE TWENTIETH CENTURY. A QUARTERLY JOURNAL OF SCIENTIFIC WORK AND THOUGHT. Edited by H. E. ARMSTRONG, Ph.D., LL.D., F.R.S., J. BRETLAND FARMER, M.A., D.Sc., F.R.S., and W. G. FREEMAN, B.Sc., F.L.S. Illustrated. 176 Pages. 5s. net. THE USE OF LIQUID AMMONIA AS A SOLVENT. THE DEGENERATION OF ARMOUR IN ANIMALS. THE ORGANISMS OF THE SOIL. E. H. L. SCHWARZ, JOHN MURRAY, ALBEMARLE STREET, W. LEWIS'S CIRCULATING MEDICAL SCIENTIFIC LIBRARY SUBSCRIPTION, TOWN OR COUNTRY, FROM ONE GUINEA. CATALOGUE OF THE LIBRARY. New Edition, revised to end of 1907. THE LIBRARY READING-ROOM is open daily for the use of subscribers. London: H. Telegrams: "Publicavit." W.C. Telephone: 10,721 Central. THE VOLCANIC ORIGIN OF COAL AND MODERN GEOLOGICAL THEORIES. By COL. A. T. FRASER (late R.E.). LONDON: ROBERT BANKS & SON, RACQUET COURT, FLEET STREET, E.C. MAN An illustrated monthly record of Anthropological Science, 1/- per part, 10/- a year, post free anywhere. PRINCIPAL CONTENTS JULY ISSUE. ORIGINAL ARTICLES: Notes on the Hair and Eye Colour of 591 Children of School Age in Surrey (Illustrated). BARBARA FREIRE-Marreco. — Daniel John Cunningham (with Plate). Prof. ARTHUR THOMSON. REVIEWS: Anthropology and the Classics.-The Origin and Develop ment of the Moral Ideas.-Textes Magiques Malgaches.-Religions, Mœurs et Legendes. London: The Royal Anthropological Institute, 3 Hanover Square. NOTICE. A new volume of NATURE (the 81st) C. Vol. 80 will be published shortly ST. MARTIN'S STREET, LONDON, W.C. THE LATE PROF. SIMON NEWCOMB Proof copies of the Photogravure Portrait of this eminent astronomer (issued in the series of Scientific Worthies) can be supplied by the Publishers of NATURE at 5s. each, or by post for 5s. 3d. C. A list of the portraits contained in the Series will be sent free to any address by the publishers on receipt of a postcard. Office of "Nature," St. Martin's Street, London, W.C. STANDARD BOOKS ON GENERAL BIOLOGY. Elementary Instruction in Practical Biology. By the Right Hon. T. H. HUXLEY, F.R.S.. assisted by H. N. MARTIN, F.R.S. New Edition, revised by G. B. HOWES, F. R.S., and D. H. SCOTT, D.Sc., F.R.S. Crown 8vo. 10s. 6d. By Prof. T. JEFFERY Lessons in Elementary Biology. BARKER, D.SC., F.R.S. Illustrated. Third Edition. Crown 8vo. 10s. 6d. 6s. 6d. net. The Biology of the Frog. By Prof. S. J. HOLMES, PH.D. Crown The Frog. An Introduction to Anatomy, Histology, and Embryology. By the late Prof. A. MILNES MARSHALL, M.D., D.Sc., &c. Edited by F. W. GAMBLE, D.Sc. Tenth Edition. Illustrated. Crown 8vo. 5s. An Introduction to Nature-Study. BY ERNEST STEN A. R.C.Sc. Globe 8vo. 35. 6d. F.R.S. Globe 8vo. 3s. 6d. HOUSE, B.Sc., Round the Year. A Series of Short Nature-Studies. By Prof. L. C. MIALL, The Natural History of Aquatic Insects. Experimental Morphology. By C. B. DAVENPORT, PH.D. By Prof. L. C. MIALL, F.R.S. With Illustrations. Globe 8vo. 35. 6d. 95. net each. By Prof. 15s. net. Or, Parts I and II. Extra Crown 8vo. 7s. 6d. First Course in Biology. COLEMAN LH. BAILEY and W. M. Darwinism: An Exposition of the Theory of Natural Selection. By ALFRED RUSSEL WALLACE, O.M., F.R.S., LL.D. Crown 8vo. 75. 6d. Natural Selection: and Tropical Nature. By ALFRED RUSSEL WALLACE, O.M., F.R.S. New Edition. Crown 8vo. 75. 6d. Island Life. By ALFRED RUSSEL WALLACE, O.M., F.R.S. 8vo. 7s. 6d. New Edition. Crown The Cell in Development and Inheritance. By Prof. E. B. WILSON, PH.D. Second Edition. 8vo. 16s. net. The Living Organism. Evolution and Man's An Introduction to the Problems of Biology. By ALFRED EARL, M.A. Place in Nature. By H. CALDERWOOD, LL.D. Second Edition. 8vo. IOS. net. [Nature Series. Are the Effects of Use and Disuse In- 4s. 6d. [Nature Series. An Outline of the Theory of Organic Evolution. By Prof. M. M. METCALF, PH.D. 8vo. Ios. 6d. net. The Development of the Frog's Egg. By Prof. T. H. MORGAN. 8vo. 7s. net. Regeneration. By Prof. T. H. MORGAN. Svo. 15s. net. 12s. 6d. net. 8vo. Evolution and Adaptation. By Prof. T. H. MORGAN. By Prof. H. F. OSBORN, Sc. D., LL.D. Edited by W. K. GREGORY, M.A. 8vo. 8s. 6d. net. ¶ Advertisements intended for the issue should reach the Publishers by, at latest, the morning of Tuesday, July 20. THE ENTOMOLOGISTS' MONTHLY MAGAZINE. Price Sixpence, Monthly. Edited by G. C. CHAMPION, F.Z.S., J. E. COLLIN, F.E.S., This Magazine, commenced in 1864, contains standard articles and notes on all subjects connected with Entomology, and especially on the Insects of the British Isles. Subscription-Six Shillings per Annum, post free. London: GURNEY & JACKSON (Mr. Van Voorst's Successors), i Paternoster Row. ROBERT ADKIN, F.E.S. DR. D. SHARP, F.R.S., F.E.S. &c. G. H. VERRALL, F.E.S. W. F. KIRBY, F E.S. G. W. KIRKALDY, F. E.S. W. J. LUCAS, B.A., F.E.S. Founded by the late Edward Newman in 1840, this Journal has been the popular organ of British Entomologists since 1864. Its contents deal chiefly with the home fauna, but there are frequent articles and notes on matters of interest pertaining to the Entomology of various parts of the world. Published on the first of each month. Price 6d. Subscription, 6s. per annum post free to any count London: WEST, NEWMAN, & CO., 54 Hatton Garden, E C. London: SIMPKIN, MARSHALL, HAMILTON, KENT & CO., Ld. NATURE. The number for last week (July 8) contained :— Ruwenzori and Central Africa. By SIR H. H. JOHNSTON, G.C.M.G., K. C. R. The Planet Mars, 1890-1901. By Dr. WILLIAM J. S. LOCKYER. The Geometry of Forces. By SIR ROBERT S. BALL, The Distribution of Gold Ores. By J. W. G. |
