Anyone sending a sketch and descrintion may quickly ascertain our opinion free whether an invention is probably patentable. communications strictly confidential. Handbook on Patents sent free. Oldest agency for securing patents. Patents taken through Munn & Co. receive special notice. without cbarge. in the Scientific American. A handsomely illustrated weekly. Largest cir. culation of any scientific journal. Terms, 3 a year; four month " 1. Sold by all newsdealers. MUNN & Co.361 Broadway,New York Branch Office (25 F St. Washington. D. C. the Government of South Australia. Adelaide: Printed by C. E. Brostow. 1901. Pp. xv., 81. 'DIFFEKENTIAL" '03. Case Sehool of Applied Science. Pp. 178. Square 8vo. PAINT AND COLOR MIXING. By Arthur Seymour Jennings. London: E. &. F. N. Spon, Ltd. New York: Spon & Chamberlain_ 1902_ Pp. 94. AMEHICAN FOOD AND GAME FISHES. A Popular Account of All the Species Found in America North of the Equator. With Keys for Ready Identification, Life Histories and Methods of Capture. By David Starr Jordan, Ph.D., and Barton Warren Ever-mann, Ph.D. New York: Doubleday, Page & Co_ 1902. Large 8vo. Pp. xlix., 573_ Price 4. rrhe names of Prof. David Starr Jordan and Prof. Barton Warren Evel'mann are in themselves a sufficient guarantee of the high charader of this hook. As it stands, the work comprises what might be termed a popular manual of ichthyology. The publishers have seen to it that the book has appeared in a most admirable dress. The printing is excellent and the illustrations good and elear. PRINCIPLES OF SANITARY SCIENCE AND THE PUBLIC HEALTH. By William T_ Sedg-wick, Ph.D. New York: The Mac-millan Company. London: Mac-millan & Co., Ltd_ 1902. Pp. xix., 368. 8vo. Price 3. The present volume is the direct outgrowth of a course of lectures on sanitary science and public health given for several years by the author to senior students of the Massachusetts Institute of Technology. The volume deals with the principles rather than the arts of sanitation, and is intended to ue no more than an elementary treatise on the 8ubjeet. It contains, howevel', some new inaterial and some old material treated from new points of view. The author tells us he has chiefly sought to bring together and to present in a simple and logieal form the fundamental scientitk principles on which the great praetieal arts of modern sanitation rest. LIGHTING BY ACETYLENE. A Treatise for the Practical Lighting Engineer. By Frederick Dye, M.R.I. London: E. &. F. N. Spon, Ltd. New York: Spon & Chamberlain. 1902. 12mo. Pp_ xit, 188. Price 2.50. Nir. Dye has prepared a short book which may be said to contain the most recent information that has been gathered on the subject of acetylene gas. The book's chief merit is its terseness. The illustrations might he improved, although the appearance of the work on the whole is good. ARCHITEKTONISCHE HOCHBAUMUSTER- HEFTE. Sammlung XI., 1. Teil. Mod-erne Einfamilienhauser und Villen. Leipzig: Carl Scholtze. 16 plates with description. This installment of a well-known work deserves the consideration of Alneriean architects. The plans and elevations presented are well designed and exhit architectural ideas, many of which are new in this country. HAXDBOOK FOR RAILWAY ENGIXEERS. By H. B. Andrews, C.E. Boston and New York: John Wiley & Sons. 1902. 32mo. Pp. 202. Price 1-25. This is another handbook added to the constantly Increasing list. It contains the usual geometrical and trigonometrical formulae, and gives transition curve tables, track construe, tion tahles, strength of wooden beams and columns, electrical formulae and tahles, and in general. information that is of service in street railway designs and street railway maintenance. EXPERIMENTS IX AERODYNAMICS. By S. P_ Langley. Second Edition_ Washington: Published by the Smithsonian Institution. 1902. Large 4to. Pp. 115. lhe value of Prof. Langley's contributions to aerodynamics and the influence which his olYn experiments in solving the prohlem of ar tificial flight have had upon the investigators cannot be over-appreciated. In the handsome volume which lies hefore us, Prof. Langley has presented with a clearness, conciseness, and, above all, with a modesty that is charaeteristic of him, the results of the very elaborate in vestigation whleh he carried out. We regret that the very limited amount of space at our disposal prevents us from devoting to the work a review commensurate with its importance. THE NAV1GATOU AU MAHINERS' GUIDE. A Handy Reference Work for the Use of Navigators, Yachtsmen and Stu dents of Navigation. Explaining How to Find Latitude and Longitude by Observation and Many Other Use ful Calculations and Tables. By Capt. R. M. Pugsley. Published by New Jersey Paint Works. Pp. 152. Price 2. This is one of the handiest guides that has ever come to our notice. It gives jus the kind of information that the amateur yachtsman wants. We are sorry to see, how ever, that its pages are liberally interspersed with advertiSing matter that might well hav been relegated to the end of the book.