FIDELITY TRUST COMPANY Nos. 325-331 CHESTNUT ST. Nos. 43-53 SOUTH FOURTH ST. Capital and Surplus, $15,000,000 Executes Trusts of Every Description. Securities and Valuables Taken for Safe Keeping. Pays Interest on Deposits. S TARR EWAGE DISPOSAL SIGNS HASSELBERG BROS. 1004 Moravian Street roth and Walnut PHILADELPHIA SAMUEL P. SADTLER & SON Consulting Chemical Experts Analyses and reports made in all branches of industrial and applied chemistry. Expert assistance in the development of chemical processes and patents, and preparation of testimony in chemical patent suits. Raw materials and waste products of manufacturing processes specially studied and reported upon. Office and Laboratory—39 S. 10th St., Phila. Will dispose of sewage in a sanitary, odorless and efficient manner at a cost for maintenance of 90% less than any other system and 100% EFFICIENCY. Endorsements by leading scientific men and various Health Boards on file for your inspection. GREEN-STARR ENGINEERING CO. Civil and Sanitary Engineers PERRY BUILDING, PHILADELPHIA, PA. Your courtesy in mentioning the Journal will be appreciated New Fourth Edition Revised and Enlarged Suplee's Mechanical Engineer's Reference Book A Hand-book of Tables, Formulas, and Methods for Engineers, Students and Draftsmen By Henry Harrison Suplee, B.Sc., M.E. Member American Society of Mechanical Engineers; Membre de la Société Des Ingénieurs Civils de France; Mitglied des Vereines Deutscher Ingenieure; Member of The Franklin Institute. Illustrated. 964 pages. 16mo. Full limp leather, round corners, gilt edges, thumb index. $5.00 net T HIS book is intended to form a standard hand-book for the mechanical engineer and the designer of machinery, supplying in convenient form the general information which is constantly required. In the new fourth edition the few errors in the previous edition have been corrected and an Appendix of forty pages added, containing a variety of useful information. 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 Development and Recent Advances of the Techno-graphic Arts. By Louis The Establishment of Photometry on a Physical Basis. By Herbert E. Ives. No. 4 387 409 437 Recent Tendencies in High School Chemistry. By Robert H. Bradbury 449 463 Notes from Nela Research Laboratory: "Overshooting" in Tungsten Lamps The Mode of Action of Ultra-violet Radiation in Injuring the Refracting Media of 477 478 Notes from the Research Laboratory, Eastman Kodak Company: 481 The Retinal Sensibilities Related to Illuminating Engineering 482 Relative Photographic and Visual Efficiencies of Illuminants 484 Notes from the Research Laboratory, General Electric Company: Committee on Science and the Arts, Stated Meeting, September 1, 1915 448, 461, 462, 470, 476, 479, 480, 487, 488, 493, 494, 502, 503 Announcements. xi-xviii Published by THE FRANKLIN INSTITUTE OF THE STATE OF PENNSYLVANIA, FIVE DOLLARS PER YEAR (Foreign Postage Additional), SINGLE NUMBERS, FIFTY CENTS. Entered at the Post-office at Philadelphia, Pa., as second-class matter. |