October 23, 1919" Flash and Sound Ranging Apparatus for the Location of Guns." BY AUGUSTUS TROWBRIDGE, PH.D., D.S.M., D.S.O., CHEV. L.H. The lecture will consist of a brief history of the development of modern methods of locating enemy artillery and the direction of the fire of friendly artillery. A non-mathematical exposition of the theory of Flash Ranging and of Sound Ranging, and the work accomplished by the ranging troops of the American Expeditionary Forces in France, both as regards the quality and quantity of information supplied to the friendly artillery. The lecture will be illustrated by lantern slides. October 30, 1919-" Wireless Telephony." BY N. H. SLAUGHTER, Engineering Department, Western Electric Company, New York, N. Y. (Formerly) Lieut. Col. Signal Corps, U. S. A. The lecture will begin with a brief review of the pre-war development of radio telephony, followed by a summary of its war-time development and application. The Airplane Radio Telegraph Set used by the Army will be described in detail. The closing part of the lecture will give an outline of the future of Radio Telephony in the military and commercial fields, with special reference to aviation. The lecture will be illustrated by lantern slides and demonstration of apparatus. Joint Meeting with Philadelphia Section, American Institute of Electrical Engineers. November 6, 1919-" American Dye Industries-Present and Future." BY BERNHARD C. HESSE, PH.D., New York City, N. Y. The coal tar dyes only will be discussed. After a summarized statement of the world-position of this industry in 1913, its development and presentday status specifically in the United States will be considered, followed by a short review of corresponding conditions abroad. The competitive conditions of today will be contrasted with those of 1913, inclusive of the altered legislative and governmental attitude toward this industry. With this as a background an attempt will be made to forecast competitive changes reasonably to be expected in the future and the action probably needful on the part of our Government and our citizens to insure in this country an as nearly self-contained and self-sustaining coal tar chemical industry, in all its most important ramifications, as the circumstances will permit. Joint Meeting with Philadelphia Section, American Chemical Society. November 13, 1919-" Nutrition and Physical Efficiency." By E. V. MCCOLLUM, PH.D., School of Hygiene and Public Health, the Johns Hopkins University, Baltimore, Md. The lecture will review briefly the results of animal experimentation in the field of nutrition studies during the past decade. The defects in the older methods of estimating the value of foods from chemical data will be explained. The dietary habits of various types of animals and of man in different parts of the world will be discussed in the light of newer knowledge, and deductions drawn concerning the most satisfactory types of diet for the promotion of physical vigor. Joint Meeting with Philadelphia Section, American Chemical Society. November 19, 1919-" The Relation of the U. S. Naval Observatory to the Navy and Shipping Interests of the Country." BY REAR ADMIRAL J. A. HOOGEWERFF, U. S. NAVY, Superintendent, U. S. Naval Observatory, Washington, D. C. The lecture will treat of the dependence of the sailor on the practical applications of astronomy. A short account will be given of the U. S. Naval Observatory and its routine work. The war-time activities of the Naval Observatory will be reviewed briefly. Illustrated by lantern slides. December 4, 1919-" Destruction of French Coal Mines and Their Rehabilitation." BY GEORGE S. RICE, Chief Mining Engineer, Bureau of Mines, Department of the Interior, The destruction of French coal mines in the Nord and Pas-de-Calais districts was of two kinds, battle and systematic, systematic destruction far exceeding the destruction incident to battle. The collieries wrecked by the Germans produced, prior to the war, 20 million tons of coal per annum. French engineers estimate that it will require five years, on an average, to place the mines on an operating basis, and ten years to recover their normal output. The character of the destruction will be described, and the engineering problems of restoration discussed. The lecture will be illustrated by lantern slides made from photographs taken by the lecturer, and official photographs furnished by the French Government. December 11, 1919-" Motor Fuels." By E. W. DEAN, PH.D., Petroleum Chemist, Bureau of Mines, Pittsburgh, Pa. A discussion of the production, properties, and utilization of fuels employed in mobile types of internal combustion engines. Chief emphasis will be given to fuels derived from petroleum. December 17, 1919-" The Construction Division of the Army." BY BRIGADIER GENERAL R. C. Marshall, Jr., U. S. A. Chief of Construction Division. A brief review will be given of the origin and labors of the Construction Division supplemented by a description of some of the larger projects necessitated by the entry of this country into the world war. Details and statistics in regard to costs, time consumed in construction, and the magnitude in general of the work will also be touched on. Illustrated by lantern slides. Joint Meeting with Philadelphia Association of Members, American Society of Civil Engineers. January 8, 1920—" The Physics of Flight." BY DAVID L. WEBSTER, PH.D., Captain, Aviation Section (flying status), Signal Officers' Reserve Corps. Assistant Professor of Physics, Massachusetts Institute of Technology, Cambridge, Mass. The work of piloting an airplane is essentially that of applying in practice certain principles of physics that are not in themselves at all complicated, but only somewhat unfamiliar to the novice, and apparently disconnected from ordinary mechanics. For this reason, and because the quickness of airplane maneuvers makes it out of the question to apply arithmetic as an aid to flying, the value of a knowledge of physics in this art is often overlooked. The fundamental physical principles of flight and their relation to more familiar phenomena will therefore be discussed briefly, and it will then be shown how they can be applied by the pilot as an aid to the proper understanding and handling of his machine. The principles of stability and of acrobatics will also be discussed. Illustrated by lantern slides. Joint Meeting with the Aero Club of Pennsylvania. January 15, 1920-" The Audion-Its Action and Some Recent Applications." BY LEE DE FOREST, PH.D., Sc.D., New York, N. Y. A brief outline of the history of the Audion and its development, from the original gas flame detector, through the two-electrode vacuum detector and valve, to the three-electrode relay, or modern Audion. The applications of the Audion as a telephone repeater; as a generator of alternating current of low or high frequency. As applied to autodyne and heterodyne receiving, with discussion of theory and operation. As a transmitter for radio telephone and telegraph; in the Air Service: in Naval Service of the U. S. and Allies during the war; in directional receiving, and in "wired wireless." For generation of musical currents; for tuning forks and small motor control, etc. General survey of the influence of the Audion on the past and future of the art of transmission of intelligence. Joint Meeting with Philadelphia Section, American Institute of Electrical Engineers. January 21, 1920-" U. S. Naval Aircraft." BY J. C. HUNSAKER, ENG.D., Commander, Construction Corps, U. S. Navy. A discussion of the development of the seaplanes, airplanes, balloons and airships for the Naval Air Service as influenced by Naval requirements, together with some account of the engineering investigations upon which the design is based. Illustrated by lantern slides. Joint Meeting with the Aero Club of Pennsylvania. January 29, 1920-" Fundamental Principles to be Considered in the Heat Treatment of Steel." BY ALBERT SAUVEUR, B.S., Professor of Metallurgy and Metallography, Harvard University, and during the war, Director, Division of Metallurgy, Technical Section, United States Air Service, A. E. F., France. In this lecture the fundamental principles underlying the heat treatment of steel will be described and discussed with special reference to the results of recent investigations and to apparent exceptions to the general rules. The influence of work upon the microstructure and physical properties of steel will also be considered, as well as the tests to be applied for its study. The lecture will be illustrated by means of charts and lantern slides. February 5, 1920-" Helium." BY RICHARD B. MOORE, B.S., D.Sc., Physical Chemist in the U. S. Bureau of Mines and Superintendent of the Colorado Station. The lecture will give an outline of the history, chemical and physical properties of the rare element helium. It will also describe the Government's work in the extraction of helium in quantity from natural gas as a substitute for hydrogen in dirigibles and balloons, and will outline its possibilities for war and commercial use. The lecture will be illustrated by experiments and lantern slides. Joint Meeting with Philadelphia Section, American Chemical Society. February 18, 1920-" The Structure of Atoms and its Bearing on Chemical Valence." BY IRVING LANGMUIR, PH.D. Research Laboratory, General Electric Company, Schenectady, N. Y. Joint Meeting with Philadelphia Section, American Chemical Society. February 26, 1920-" Artillery of the A. E. F." BY MAJOR GENERAL C. C. WILLIAMS, Chief of Ordnance, U. S. Army, War Department, Washington, D. C. The lecture will treat of a description of the types of Artillery equipment used by the American Expeditionary Forces in France, with a brief discussion of their uses and the reasons for their adoption. The lecture will be illustrated by lantern slides. March 4, 1920-" The Manufacture of Plate Glass." By G. A. RANKIN, Chemist, Washington, D. C. The lecture will deal with the various operations involved in the manufacture of plate glass; the making of the pots; the preparation of the glass batch; the construction of the melting furnaces; the melting and fining of the glass; casting and rolling glass plates; the annealing of the plates; the grinding and polishing; the preparation of rouge for polishing; the inspection of the finished product. Illustrated by lantern slides. Joint Meeting with Philadelphia Section, American Chemical Society. March 11, 1920-" Photographing Sound Waves from Large Guns and Projectiles." BY DAYTON C. MILLER, D. Sc., Professor of Physics, Case School of Applied Science, Cleveland, Ohio. By permission of the Ordnance Department of the United States Army an extended series of experiments has been carried out at several Proving Grounds, relating to the pressures, velocity, and form of the sound waves produced by the discharge of guns of the largest caliber (10-inch, 12-inch and 14-inch). The entire pressure field all around the gun, from the muzzle to a considerable distance, has been explored by means of a new type of baroscope. The variation in the velocity of the explosive sound from the muzzle to distances of several miles has been determined by means of a string galvanometer in connection with special high and low pressure microphones and a special photorecording device. These experiments give a new determination of the velocity of sound in free air. The form of the sound wave has been photographically recorded by means of a new portable phonodeik; the records give information of great interest as regards the relation of the pressure to the "vacuum part of the wave, and as to the number of vibrations, frequency, etc. The photographs not only show the sound wave proper but also the "crack" produced by the motion of the projectile through the air; the latter records give interesting results as to the velocity of the projectile itself as well as other information. The lecture will explain the methods and give the results of the investigations, and will be illustrated with apparatus, experiments and slides. March 17, 1920-" The Induction Electrical Furnance." BY G. H. CLAMER, The lecture will trace the development of the induction furnace, in its various forms, from the original conception by Colby of the single-turn open-ring type furnace, to the latest developments by Dr. E. F. Northrup in the use of high frequency induction heating. Will include a discussion of the various fluid motions due to electro-dynamic forces, and the use which is made of such forces in several forms of induction furnaces. Will treat more particularly of the commercial operation of induction furnaces, using both low and high frequency currents. The lecture will be illustrated by lantern slides. Joint Meeting with Philadelphia Section, American Institute of Electrical Engineers. |