IMPORTANT ANNOUNCEMENT. D'Arsonval's Latest (1904) Apparatus, DISPENSING WITH COILS & INTERRUPTERS. X-RAYS & HIGH-FREQUENCY CURRENTS. (Protected by Numerous Patents.) SILENT IN WORKING. SIMPLE IN MANIPULATION. This apparatus has been already installed by many of the chief workers in Electro-Therapeutics in France and England. Descriptive Pamphlet gratis on application from the Sole Agents for Great Britain and its Colonies THE MEDICAL SUPPLY ASSOCIATION, 228 GRAY'S INN ROAD, LONDON, W.C., LIGHTING LARGER INSTALLATIONS GIVE STILL MORE REMARKABLE RESULTS. Electric Current for 100 16-c.p. lamps can be obtained for ONE PENNYWORTH of fuel per hour by using a CROSSLEY CROSSLEY MANCHESTER. WATSON'S MICROSCOPES & OBJECTS. Watson's New "Club" Microscope. An Instrument of full size of most modern design. Especially arranged for the use of Amateurs. Monocular, £15; Binocular, £18. Watson's well-known Van Heurck and Edinburgh Student's Micro- The Watson-Conrady Condenser System is of new computation, and for the Microscopist. Everything For all the above see WATSON'S 158-page Catalogue of Microscopes, sent New Slide of Radium for Microscope. Shows Scintillations Trypanosoma Brucei (Sleeping Sickness) each s. d. 5 6 40 40 30 26 5/- to 21 0 Exquisite arranged groups composed of Diatoms, Spicules, &c., according to size, from Scales and Hairs of Insects arranged to represent Sprays, Bouquets, and Vases of Flowers, always interesting and attractive... 7/6, 15/-, 21/- and 42 0 Write for Catalogue No. 3 of Micro. Objects, together with newly published supplementary list of Slides, giving details of recently added specimens, post free. post free. SPINTHARISCOPE for observing the Scintillations of Radium. The very best. Price 21/SPECIALITIES: STRUTT'S RADIUM CLOCK. Price according to quantity and quality of Radium included. RADIUM of MAXIMUM activity in stock, also of medium and moderate activities. Send for particulars. W. WATSON & SONS, 313 HIGH HOLBORN, LONDON, W.C. BRANCH-16 Forrest Road, Edinburgh. J. H. DALLMEYER, Ltd., 25 Newman St., LONDON W. Printed by RICHARD CLAY AND SONS, LIMITED, at 7 & 8 Bread Street Hill, Queen Victoria Street, in the City of London, and published by MACMILLAN AND CO., LIMITED, at St. Martin's Street, London, W.C., and THE MACMILLAN COMPANY, 66 Fifth Avenue, New York.-THURSDAY, Jan. 19, 1905. "NATURE" says: "The new illustrated catalogue of physical appara tus just issued by Messrs. F. E. Becker and Co. (Messrs. W. and J. George, Ltd.) is likely to prove indispensable in the physical laboratories of all our schools and colleges. It runs to 628 large pages, and is strongly bound in cloth. Full particulars are provided, not only respecting the apparatus required in elementary and advanced physical teaching, but also concerning that necessary to the physicist in his research work. All branches of physics are included, and the instruments throughout are explained by excellent illustrations and concise descriptions, and, what is of prime importance, the figure and its appropriate text are close together." 66 KNOWLEDGE" says: "Messrs. F. E. Becker and Co. (W. and J. George, Ltd., Successors) have sent us a copy of their new list of apparatus in the various departments of Physics, including Sound, Light, Heat, Magnetism, Electricity, Mechanics, &c. This exhaustive catalogue consists of over 600 pages and some 4000 illustrations. One of its noteworthy features is that the requirements of science teaching in this country and its colonies are always kept in view, and the articles listed cover the latest developments in their subjects. The method adopted in the list itself, together with the completeness of the index, is such as to make reference to it simple and expeditious." "SCHOOL WORLD" says: The science-master in every grade of school should possess a copy of the new catalogue of Messrs. George, for he will find here particulars as to the available apparatus in sound, light, heat, magnetism, electricity, mechanics, and other branches of physics, with information as to price and other necessary details. There is a profusion of well-drawn illustrations, which, together with the clearly expressed descriptions, will serve to explain to any buyer exactly what he is purchasing. This excellent catalogue will form a valuable addition to the reference library of any physical laboratory." 66 "CHEMICAL NEWS" says: 'Messrs. F. E. Becker and Co. (W. and J. George, Ltd., successors) have just issued a new Illustrated and Descriptive Catalogue of Physical Apparatus, &c., manufactured by them. This is the largest and best English catalogue of its kind printed, and comprises some 630 pages, and over 4000 illustrations; herein will be found all the newest up to date apparatus with all the latest improvements as manufactured at their works, while all obsolete apparatus has been omitted. The whole catalogue is arranged in a very clear manner under a number of principal headings, such as Magnetism, Heat, Sound, Light, Mechanics, Electricity, Pneumatics, Meteorology, X-ray Apparatus, &c., and a good index is provided; in fact, everything possible has been done to make this as perfect a guide as possible to users of apparatus in the subjects touched upon." NOW READY. With Illustrations, 2s. 6d. net, by post 2s. 9d. X-RAYS: TEXT-BOOKS OF PHYSICAL CHEMISTRY. EDITED BY SIR WILLIAM RAMSAY, K.C.B., F.R.S. "Collectively the manuals will form an adequate record of the present state of knowledge in a large and important field of chemistry. We heartily wish well to Sir William ance of the succeeling numbers of the series." -GLASGOW HERALD. THEIR EMPLOYMENT in CANCER and Ramsay's venture, and look with interest for the appear other DISEASES. BY RICHARD J. COWEN, L.R.C.S.I., L.R.C.P.I., &c. London: H. J. GLAISHER, 57 Wigmore Street, W. NOW READY. With 815 Illustrations from Photomicrographs. Sup.-Roy. 8vo. Price 318. 6d. STUDIES IN HETEROGENESIS. By Dr. CHARLTON BASTIAN, F.R.S., Consulting Physician to University College Hospital, and the National Hospital for the Paralysed and Epileptic. WILLIAMS & NORGATE, 14 HENRIETTA STREET, W.C. LATEST PUBLICATIONS OF THE ZOOLOGICAL SOCIETY OF LONDON. The " Zoological Record (Vol. 40), being Records of Zoological Literature relating chiefly to the year 1903. Edited by DAVID SHARP, F.R.S. Price to Fellows, 255.; to the Public, 305. The several sections of the volume are now issued separately, and can be obtained at the Society's Office, 3 Hanover Square, W., where communica. tions concerning this publication should be made only. With 30 Original Illustrations. Price 2s. 6d. A Guide to the Prevention and Control of Dental Diseases. BY THE SAME AUTHOR. The DISEASES of CHILDREN'S TEETH. Well Illustrated. Price 7s. 6d. SEGG & CO., 289 and 291 Regent 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. 85 PRAED STREET, LONDON, W. SCIENTIFIC AND EDUCATIONAL BOOKS NEW & SECOND HAND. TARY and ADVANCED SCIENTIFIC BOOKS at about HALF PUBLISHED PRICE. Mathematical, Theological, and Foreign Books. KEYS AND TRANSLATIONS. 104 CHARING CROSS ROAD, THE PHASE RULE AND ITS APPLICATIONS. By ALEX. FINDLAY, M.A., Ph.D., D.Sc., Lecturer and Demonstrator in Chemistry, University of Birmingham. WITH FIGURES IN THE TEXT. Together with AN INTRODUCTION TO THE STUDY OF By SIR WILLIAM RAMSAY, K.C.B., F.R.S. "It is not an easy subject to treat, and to do so in a clear, concise, and orderly manner which can be understood by anyone who possesses a knowledge of the principles of physical chemistry, is indeed difficult. This is the task which Dr. Findlay set himself, and he has been completely successful."-Colliery Guardian. "If the succeeding issues are as excellent as this, then a notable and indispensable addition will be made to the library of the student of chemistry."-Journal of Education. SIR WILLIAM RAMSAY'S INTRODUCTION TO PHYSICAL is also issued separately, price Is. net. ... 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NEW RAPID MERCURY W. WILSON, INTERRUPTER. This is an improved Double Dipper Break with a simple and reliable method of raising and lowering the mercury. Special attention is drawn to the motor, which is of English make, and not a toy. Price £5 50 If you need a SWITCH A. C. COSSOR, St. Louis Fxhibition, 1904. Maker of SPECTROSCOPES, SPECTROMETERS, GONIOMETERS, OPTICAL BENCHES, OPTICAL AND OTHER BEST WORK. MODERATE PRICEL Price List Free. 1, BELMONT STREET, CHALK FARM, N.W. THE MILK CHOCOLATE "PAR EXCELLENCE." FIVE BOYS" Fry's MILK CHOCOLATE "Unrivalled as a Chocolate Confection."-Medical Magazine. BRITISH MILK AND BRITISH LABOUR. RICHARD CLAY AND SONS, LTD, BREAD ST. HILL, E.C., AND BUNGAY, SUFFOLK. |