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Several features make this the one up-to-date complete accurate work for mechanical engineers,-more space has been devoted to Mathematics than in any other similar reference book in English,-the subject of machine design is very amply treated,-the arrangement of the matter is unexcelled, and fully illustrated, which together with the complete thumb index, makes it just the book for quick reference. Send for Bulletin of New Scientific Books J. B. LIPPINCOTT COMPANY Publishers Philadelphia Your courtesy in mentioning the Journal will be appreciated of The Franklin Institute DEVOTED TO SCIENCE AND THE MECHANIC ARTS Edited by R. B. OWENS, E.E., M.A., D.Sc., F.R.S.C. The Production of Light by Animals. By Ulric Dahlgren E. H. Sanborn 513 Recent Researches in Electricity at the Bureau of Standards. By E. B. Rosa 539 561 The Conductivity and Viscosity of Solutions of Electrolytes in Formamid. 567 On the Retention of Activity by Urease and by Oxidase after Exposure to 603 Notes from the U. S. Bureau of Standards: A New Relation from Planck's Law 607 The Microstructural Changes Accompanying the Annealing of Bronze (Cu88, 607 Compressive Strength of Portland Cement Mortars and Concretes 608 Standard Test Specimen of Zinc Bronze (Cu88, Sn10, Zn2). Part II-Micro Earth Resistance and its Relation to the Electrolysis of Underground Structures 614 615 Notes from Nela Research Laboratory: The Relation between Spectral Color and Stimulation in the Lower Organisms. 617 619 The Franklin Institute: Stated Meeting, October 20, 1915 623 Committee on Science and the Arts, Stated Meeting, October 6, 1915 Section of Physics and Chemistry, Stated Meetings, October 7 and October 14, 624 624 Minute of the Board of Managers on the Death of John T. Morris. FIVE DOLLARS PER YEAR (Foreign Postage Additional). SINGLE NUMBERS, FIFTY CENTS. |