Pearce, Milton J. Rosenau, Edward R. Stitt, Wm. H. Welch, H. Gideon Wells. Agriculture: Raymond Pearl, chairman. Edwin W. Allen, Carl L. Alsberg, Henry P. Armsby, Eugene Davenport, Edward M. East, L. O. Howard, L. R. Jones, Whitman H. Jordan, Karl F. Kellerman, Jacob G. Lipman, L. B. Mendel, Erwin F. Smith, Theobald Smith, W. J. Spillman, William M. Wheeler. Physiology: W. B. Cannon, chairman. SCIENTIFIC NOTES AND NEWS IN accepting the resignation of Professor R. C. Carpenter from the faculty of Sibley College, Cornell University, the trustees have adopted the following resolution: Resolved, that the trustees in accepting the resignation of Professor Carpenter, express their high appreciation of his services to the university for nearly thirty years. As a pioneer in the field of experimental engineering he is held in the highest esteem by all mechanical engineers, and by his writings in this field he has made an assured place for himself in the annals of his profession. As a teacher and investigator he is affectionately remembered by many generations of students and his retirement from the faculty of Sibley College will be viewed with great regret by all of his colleagues. THE portrait of Professor R. D. Salisbury, planned for by his former students, was presented to the University of Chicago on the afternoon of February 8. Dr. T. C. Chamberlin gave a sketch of Professor Salisbury's life, emphasizing his early work as a student and his contribution as a man of research. Professor W. W. Atwood, of Harvard University, spoke in behalf of the students, emphasizing the great work of Professor Salisbury as an educator and formally presented the portrait to the university. Professor Salisbury, at the request of President H. P. Judson, who presided, replied briefly, and on behalf of the university the president accepted the gift. DR. JOSEPH A. BLAKE, formerly professor of surgery in Columbia University, who has rendered distinguished services at Neuilly and at Ris-Orangis, has accepted an invitation from the French government to become head of the great Doyen Hospital. THE officers of the Illinois State Academy of Science elected for the ensuing year are as follows: President, Dr. J. C. Hesler, James Millikin University, Decatur. Vice-president, J. H. Ferris, Joliet. Treasurer, Professor T. L. Hankinson, Eastern State Normal School, Charleston. Secretary, Professor J. L. Pricer, State Normal University, Normal. THE following officers of the Chemical Society, London, for 1917-18, have been proposed by the council: President, Professor W. Jackson Pope; New Vice-presidents, Colonel A. Smithells and Professor Sydney Young; New Ordinary Members of Council, Professor H. C. H. Carpenter, Professor A. Findlay, Professor A. Harden and Dr. T. A. Henry. MR. F. J. CHESHIRE has been elected president of the Optical Society, London. A GOLD medal has been awarded by the French government to Professor Landouzy for his long and ceaseless study of tuberculosis and means to combat it. DR. ROY G. PEARCE, formerly assistant professor of physiology, college of medicine, University of Illinois, Chicago, is now a member of the research laboratory of the medical clinic, Lakeside Hospital, Cleveland. Dr. Stanley P. Reiman, formerly resident pathologist, Lakeside Hospital, has been appointed Hanna research fellow in pathology in the school of medicine, Western Reserve University. DR. ROBERT GRANT AITKEN, astronomer in the Lick Observatory, has been granted by the University of California four months' leave of absence to go to the Atlantic coast to complete arrangements for the publication of his work on the double stars. HENRY HINDS, geologist and acting chief of the section of eastern coal fields of the U. S. Geological Survey, has left the government service temporarily in order to take up private oil work in Costa Rica and neighboring republics. DR. A. J. CARLSON, professor of physiology in the University of Chicago, read a paper at the February meeting of the Kansas Chapter of Sigma Xi on "The Nature of the Hunger Mechanism." On the evening of March 24 Professor Wallace W. Attwood, of Harvard University, will conduct a lecture conference at the Brooklyn Institute of Arts and Sciences on "Gold Mining in Alaska." The lecture will be illustrated. DR. W. S. COOPER, of the University of Minnesota, gave a lecture on February 23 before the Geographic Society of Chicago on "The Vegetation of the Glaciers of Alaska." On March 23, Professor Robert G. Aitken, of the Lick Observatory, will speak on "The Work of two Mountain Observatories." called ptomaine poisoning, with special reference to canned goods. The offer has been accepted by the university, with the understanding that the investigation shall be conducted and the results thereof published with entire academic freedom. The study will be made at the Medical School under the direction of Dr. M. J. Rosenau, professor of preventive medicine and hygiene. The national research council of the National Academy of Sciences is supervising the investigations on this subject. The advisory committee of the council consists of Professors John J. Abel, of Johns Hopkins University; Reid Hunt, of Harvard University; H. Gideon Wells, of the University of Chicago; Eugene Opie, of Washington University; Lafayette B. Mendel, of Yale Univer MR. A. CASTON CHAPMAN delivered a lecture, sity, and Frederick T. Novy, of the University entitled "Some Main Lines of Advance in the Domain of Modern Analytical Chemistry," to the Chemical Society, London, on March 15. Dr. Horace T. Brown will lecture on "The Principles of Diffusion: their Analogies and Applications," on May 17. THE library of the late Professor Hugo Münsterberg has been given to Harvard University by a group of his friends. The library consists of about 10,000 books, reprints, pamphlets, manuscripts, charts and other papers. Among the 3,000 books in the collection are the latest and most valuable ones on experimental and applied psychology, especially those bearing on phases of the subject to which Professor Münsterberg had devoted his time. GEORGE MASSEE, formerly of the Royal Botanic Garden, Kew, died on February 17, at the age of sixty-seven years. DR. A. BATTELLI, professor of experimental physics at the University of Pisa and a member of the Italian national legislature, has died at the age of fifty-five years. DR. FRIEDRICH HAHN, who occupied the chair of geography at Königsberg, has died at the age of sixty-five years. THE National Canners' Association has offered Harvard University the sum of $20,000 annually for a period of three years to carry on an investigation of food poisoning or so of Michigan. THE Council of the New York Academy of Sciences has voted that because of the unsettled condition of our international affairs the Centennial Celebration, planned for the second week of the coming May, be deferred without date. It was, however, voted that a centennial meeting be held some Monday evening in May at which emphasis will be placed on the history of the academy. The president was authorized to obtain a speaker for this Centennial Meeting; and was requested, in consultation with the other members of the committee on history to prepare a digest of historical data for the occasion. THE lieutenant-governor of the Punjab laid the foundation stone of the new building of the Society for Promoting Scientific Knowledge at Lahore on January 30. The site for the new headquarters of the society has been given by the Lahore municipality and a sum of Rs. 14,000 has been raised by subscription. THE department of chemistry of the New York City College, of which Professor Charles Baskerville is the head, has announced a series of lectures to be offered during the spring semester. These lectures are open to the public, and will be held on Friday afternoons at three o'clock in the Doremus Lecture Theater, 140th Street and Convent Avenue. The following is the list of lectures. February 16, "From Ore to Finished Pipe" (illustrated with motion pictures), by Mr. C. F. Roland, New York representative, metallurgical department, National Tube Co. March 2, "New Method for Nitrogen Fixation," experimental, showing utilization of home-made apparatus, by Dr. J. E. Bucher, professor of chemistry, Brown University. March 16, “Chemical Structure and the Biological Function of Tissue Elements," by Dr. P. A. Levene, Rockefeller Institute. March 23, "The Conservation of Pine Forests through the Methods of Chemical Research (illustrated by specimens and stereopticon), by Dr. Chas. H. Herty, editor of the Journal of Industrial and Engineering Chemistry. March 30, "The Getting of Wisdom," by Dr. H. K. Mees, director research department, Eastman Kodak Co. April 13, "Colloids in Pharmacy" (illustrated and experimental), by Dr. John Uri Lloyd, manufacturer, chief chemist, investigator and novelist. April 27, "Some Chemistry of the Tropics" (illustrated from recent observation), by Dr. L. H. Friedburg, professor emeritus of the College of the City of New York. DR. THOMAS H. HAINES, professor of nervous and mental diseases at Ohio State University, has five months' leave of absence from his work at the university and from the Bureau of Juvenile Research, and is making a state survey of mental defectives in Kentucky. A state commission on the feebleminded was appointed in May, 1916, by Governor Stanley in accordance with a resolution adopted by the General Assembly in March, 1916. Dr. Haines was appointed director of the survey and sent to the commission in Kentucky by the National Committee for Mental Hygiene, and the Rockefeller Foundation, without cost to the state of Kentucky. Kentucky presents a peculiarly fertile field in which to secure social economics in the management of defectives. By the terms of the Pauper Idiot Act, the substance of which has been on the statute books since the second year of the commonwealth, 1793, any person who is proved to be without estate and mentally feeble, to the satisfaction of a jury, and is so certified to the state auditor, may draw annually from the state treasury, through his committee seventy-five dollars for his maintenance. Last year more than twentytwo hundred such pauper idiots cost Kentucky by this means alone $165,000. This method is said to encourage the propagation of the mentally incompetent. MR. AND MRS. GILBERT H. GROSVENOR have given to the American Association to Promote the Teaching of Speech to the Deaf a trust fund of $5,000 to establish an "Alexander Graham Bell Grosvenor Memorial Fund," in memory of their second son, who died March 6, 1915. In accepting this memorial fund the directors resolved that the income shall be used in paying for the publication and distribution of literature that will help parents to intelligently train and teach deaf children in the home prior to school age, and that every publication paid for from the income of this fund shall bear on the title page an inscription stating that it is a publication. of the Alexander Graham Bell Grosvenor Memorial Fund. Following a suggestion from the donors, the directors decided to offer $300, a sum equivalent to the first year's income, for the best essay on the subject of "Teaching and Training Little Deaf Children in the Home." A decision on the essays submitted will shortly be made by the judges, who are Mr. and Mrs. Edmund Lyon, Rochester, N. Y., Dr. and Mrs. A. L. E. Crouter, Mr. Airy, Philadelphia, Pa., and Mr. and Mrs. Gilbert H. Grosvenor, Washington, D. C. UNIVERSITY AND EDUCATIONAL WASHBURN COLLEGE at Topeka, Kansas, has just added $500,000 to its permanent endowment fund. Of this sum $200,000 was contributed by citizens of Topeka, $200,000 consists of contributions secured by President Womer outside of Topeka and $100,000 was given by the General Education Board. THE University of California is to receive $10,000 as a library endowment by bequest from Horace Davis, president of the university from 1888 to 1890. IT has been decided to make the erection of new science buildings for the University College of North Wales, Bangor, the North Wales memorial to men fallen in the war. The cost of the scheme will be £150,000. WE learn from Nature that Mr. D. M. Forbes, who died on December 13 last, has bequeathed to the University of Edinburgh his books relating to the Philippine Islands, and the residue of his property, which, with the property abroad, will amount, it is understood, to about £100,000, for the purposes of education. THE Council of the University of Liverpool has recently received from a donor who desires to remain anonymous a sum of money sufficient partially to endow a chair of geography. The council has felt justified, under the circumstances, in establishing the chair, and a professor will be appointed in a few weeks. of force in most of our modern text-books of physics, but does not make clear just how he would "use force only in the single definite sense implied in the laws of motion." Let us take the following simple case: a ball is attached to a rubber cord, say three feet in length. A person grasps the ball and pulls it with a force F, stretching the rubber cord to a length of five feet. The strain in the cord is produced by the two forces + F and -F acting at the ends of the cord. The third law of motion covers the case. Now suppose the person swings the ball around his head at the end of the rubber cord until its velocity is great enough to stretch the cord again to a length of five feet. The stress in the cord is the same as before. The question is, what is the nature of the " reaction" which the ball is exerting on the cord WALTER A. PATRICK, Ph.D. (Göttingen), of to stretch it? It is certainly a "force" F Syracuse University, has been appointed asso(otherwise the cord would not be stretched as ciate in chemistry at the Johns Hopkins Uniit is), and it is in one sense balancing the versity. After two years spent in physical equal "action" of the cord on the revolving chemical research at the Massachusetts Institute of Technology, Dr. Patrick spent a year with Freundlich, at Braunschweig, a year with Zsigmondy at Göttingen and a year as private assistant to Professor Donnan, at University College, London. DR. HOWARD T. KARSNER, professor of pathology, has been elected secretary of the school of medicine, Western Reserve University. Dr. Russell J. Collins, demonstrator of pharmacology, has resigned because of ill health. THE University of Cambridge will hereafter grant the degrees of master of letters and master of science for somewhat the same qualifications as the doctorate of philosophy is awarded by German and American universities. A proposal that the degree of doctor of philosophy be awarded was rejected. DISCUSSION AND CORRESPONDENCE WHEN IS A FORCE NOT A FORCE? THE article by Mr. Gordon S. Fulcher in SCIENCE for November 24, 1916, calls attention in a most timely way to the vagueness which characterizes the discussion of the idea ball, which we know as centripetal force. Is the "centrifugal force" (inertia-reaction of the ball) in this case a force in the "single definite sense implied in the laws of motion"? Does the third law also cover this case? We usually define force as that which produces (or tends to produce) a change in the condition of motion of a mass, either in magnitude or in direction. Certainly inertia-reaction might not come under this definition, but undoubtedly our definitions of force are intended to describe ordinary forces-mechanical, magnetic, electrical, etc.-which can do three things: (1) oppose other forces, (2) produce acceleration, and (3) produce deceleration. The force called friction can do only the first and third of these things; it can not produce acceleration (except in indirect ways). Is friction a force in good and regular standing in the "single definite sense implied in the laws of motion"? Inertia-reaction can do only the first of these three things; it can not, by its very nature, produce either acceleration or deceleration. And yet even while it is opposing the restoring stress in the rubber cord mentioned above, we Or when in another text he is told that to every action there is always an equal and contrary action, and is then informed that an unbalanced force acting on a mass produces acceleration? Or when he reads in one of the very best of our first-year texts that "forces always occur in pairs, one of the pair being equal and opposite to the other," and yet is told a little farther on that "by an unbalanced force we mean more push or pull in one direction than the other"? Why can not we frankly admit that inertiareaction acts in one respect like a force, and is actually a kind of force, even if we continue to use the term "unbalanced force " in the sense of a force opposed only by inertiareaction? A porter pushing a heavily laden truck at uniform speed feels the reaction due to friction; if the friction suddenly vanished, he would feel the reaction due to the inertia of the truck. He might not know the difference, except that in the latter case he would succeed in giving the truck a small acceleration. But he would doubtless be greatly astonished to learn that in the first case his push was balanced by an equal counter-force, while in the second case his push was an balanced force"! un The writer finds that the clearest (if somewhat tautological) definition of force for the average student is that which produces motion, change of motion, compression and tension. Under this definition the inertia-reaction of the ball revolving at the end of the rubber cord is a force, because it produces tension in the cord. Inertia-reaction can oppose other forces, it can in that sense balance them, but it can not hold them in equilibrium, because a force opposed only by inertia-reaction always produces acceleration, positive or negative, and may for that reason be called an unbalanced force. If the drawbar pull of a locomotive is 1,000 pounds, and the sum of the opposing forces due to the friction of the wheels, journals, wind, etc., is 600 pounds, we may say that the unbalanced force exerted by the engine on the train is 400 pounds, and this produces acceleration. But the pull on the drawbar is the same in both directions-it is manifestly impossible for it to be otherwise and the backward pull is made up of 600 pounds of frictional forces and 400 pounds of inertia-reaction. ANDREW H. PATTERSON UNIVERSITY OF NORTH CAROLINA, CHAPEL HILL SCIENTIFIC BOOKS Diseases of Occupation and Vocational Hygiene. Edited by G. M. KOBER and W. C. HANSON. P. Blakiston's Son & Company. Philadelphia, 1916. Octavo. Pp. xxi +918. $8.00. Ten years ago there was no such thing as a science of industrial hygiene in the United States. During the last half of the decade Dr. Alice Hamilton, Dr. G. M. Price, Dr. E. R. Hayhurst, Mr. F. L. Hoffman and others have conducted fundamental and important investigations in this field; the American Association for Labor Legislation has organized an educational campaign which has resulted in unparalleled legislative advances; and during the past two years three good textbooks have appeared dealing with the subject -Dr. G. M. Price's "The Modern Factory," Dr. W. Gilman Thompson's "The Occupational Diseases," and the volume under discussion-besides a wealth of monographs on accident prevention and other special phases of the subject. "Diseases of Occupation and Vocational Hygiene" is the most ambitious of these works, having been prepared under the editorship of Drs. Kober and Hanson by thirty-one American and foreign specialists in various branches. Many of the topics are so treated |