56 CHARING HARVEY & PEAK, BY APPOINTMENT TO THE ROYAL INSTITU. POST OFFICE BRIDGE SETS AND MACMILLAN & CO.'S w.c. LIST. THE GEOLOGY OF SOUTH AFRICA. By F. H. HATCH, Ph.D., M.Inst.C.E., President of the Geological Society of South Africa; and G. S. CORSTORPHINE, B.Sc., Ph.D., Consulting Geologist to the Consolidated Coalfields of South Africa MINING WORLD.-"The authors are to be congratulated on their success. . . . It deserves, and will no doubt have, a wide circulation." 8vo. 21s. net. NEW AND REVISED EDITION, NOW READY. A TREATISE ON CHEMISTRY. By SIR H. E. ROSCOE, F.R.S., and C. SCHORLEMMER, F.R.S. Vol. I.-The Non-Metallic Elements. New Edition, completely revised by Sir H. E. ROSCOE, assisted by Dr. H. G. COLMAN and Dr. A. HARDEN. With 217 Illustrations. 8vo. 215. net. ATHENEUM." It is almost superfluous to say that the work maintains its original high standard, and is pre-eminent among works of its class in all languages." MARINE BIOLOGICAL ASSOCIATION The following animals can always be supplied, either living or preserved by the best methods: Sycon; Clava, Obelia, Sertularia; Actinia, Tealia, Caryophyllia, Alcyonium; Hormiphera (preserved); Leptoplana; Lineu, Amphiporus, Nereis, Aphrodite, Arenicola, Lanice, Terebella; Lepas, Balanus, Gammarus, Ligia Mysis, Nebalia, Carcinus; Patella, Buccinum, Eledone, Pectens Bugula, Crisia, Pedicellina, Holothuria, Asterias, Echinus, Ascidia, Salpa (preserved), Scyllium, Raia, &c., &c. For prices and more detailed lists apply to Biological Laboratory, Plymouth. THE DIRECTOR. WATKINS & DONCASTER, Naturalists and Manufacturers of CABINETS AND APPARATUS FOR ENTOMOLOGY, BIRDS' EGGS AND SKINS, AND ALL SPECIAL SHOW-ROOM FOR CABINETS. N. B. For Excellence and Superiority of Cabinets and Apparatus, references are permitted to distinguished patrons, Museums, Colleges, &c. A LARGE STOCK OF INSECTS, BIRDS' EGGS AND SKINS. SPECIALITY.-Objects for Nature Study, Drawing Classes, &c. Birds, Mammals, &c., Preserved and Mounted by First-class Workmen true to Nature. All Books and Publications on Natural History supplied. 36 STRAND, LONDON, W.C. (Five Doors from Charing Cross.) New Catalogue (102 pp.) just issued, post free. LANTERN SLIDES of Scientific Subjects, from 6/- per dozen. Also Hand Painted from 1/3 to 5/- each. Slides from Prints, Drawings, Photographs, &c., a Speciality. ROCKS, MINERALS, FOSSILS. For Collectors, Students, Technical Schools, Colleges, &c. COLLECTIONS IN POLISHED DEAL BOXES. 25 Specimens, 5/6; 50 do., 10/6; 100 do., 21/-; 200 do., 42/20 Coal Measure Rocks and Fossils, 12/6; do., larger, 15/-. Adapted for the Board of Education Examinations in Geology, Physiography, and Mineralogy. A large stock of Minerals, Rocks, Fossils and Microscopic Objects for NEW CATALOGUE POST FREE. THOMAS D. RUSSELL, 78 Newgate St., London, E.C. MICROSCOPICAL PETROGRAPHY. Gentlemen interested in the above study are invited to send to JAMES R. GREGORY & CO., I Kelso Place, Kensington Court, London, W., for a Prospectus of THE TWENTIETH CENTURY ATLAS OF MICROSCOPICAL PETROGRAPHY, now being issued in Twelve Monthly Parts, each Part containing Four Fine Half-Tone Plates, and also Four actual Rock Sections. Subscription in advance, either Monthly, 7/-; Quarterly, 21/-; or for the whole Series of 12 Monthly Parts & 48 Sections, £4 4s. PHOTOMICROGRAPHY for Publishers, Lecturers, Manufacturers, and general scientific research. Good work, moderate charges.-SAXBY, 91 Penny Lane, Sefton Park, Liverpool. NOTICE.-Advertisements and business letters for NATURE should be addressed to the Publishers; Editorial Communications to the Editor. The telegraphic address of NATURE is " PHUSIS," LONDON. NEW MICROSCOPIC SLIDES From the New Issue of W. WATSON & SONS' No. 3 CATALOGUE, just published. Post Free on application. SEND FOR THE ABOVE NEWLY PUBLISHED CATALOGUE OF MICRO. OBJECTS. WATSON'S CATALOGUE OF MICROSCOPES (158 pages) is of special interest to all Microscopists. post free. W. WATSON & SONS, 313 High Holborn, London, W.C. Branches-16 FORREST ROAD, EDINBURGH, and 2 EASY ROW, BIRMINGHAM. CROSSLEY'S GAS ENGINES Iinted by RICHARD CLAY AND SONS, LIMITED, at 7 & 8 Bread Street Hill, Queen Victoria Street, in the City of London, and published by MAITIAN AND CO., LIMITED, at St. Martin's Street, London, W.C., and THE MACMILLAN COMPANY, 66 Fifth Avenue, New York.-THURSDAY, September 14 15 PATENT [PRICE 15 CENTS [All Rights are Reserved. REYNOLDS & BRANSON, "DEMONSTRATOR'S" LANTERN. LABORATORY FURNISHERS and MANUFACTURING CHEMISTS. CHEMICAL AND PHYSICAL BENCH, illustrated above, as supplied Catalogue of Chemical and Physical Apparatus, 350 pp. and 1200 JOHN J. GRIFFIN & SONS, Ltd., 20-26 SARDINIA ST., LINCOLN'S INN FIELDS, NEGRETTI & ZAMBRA'S LONG RANGE BAROMETERS THE DIAGONAL BAROMETER.-In this instrument the tube is much longer than usual, and at the point on the vertical column where in ordinary Mercurial Barometers the 28 inches would be marked, the tube is bent at an angle and the remaining 3 inches of the scale-viz.: 29, 30. and 31are extended over a tube 36 inches long. The mercury now moving diagonally instead of vertically, travels over 12 inches of the tube to every inch on the vertical scale. The slightest variation, even or" to which the scale is divided, is at once noticeable and can be easily read without the aid of a vernier or magnifier. Further Particulars and Prices of this and other long range Barometers sent on application to the Manufacturers. NEGRETTI & ZAMBRA, |