February 5, 1915] 



SCIENCE 



207 



UNIVEESITT AND EDUCATIONAL NEWS 



T-HE sum of $40,000 has been given by Mr. 

 Andrew Carnegie to Allegheny College for a 

 chemical laboratory to replace the one recently 

 destroyed by fire. 



Mr. Patten, who has already given $500,- 

 000 to the medical school of ISTorthwestern 

 University, has now added $2Y,000 for scholar- 

 ships. 



Professor C. H. Peabody, head of the de- 

 partment of naval architecture at the Massa- 

 chusetts Institute of Technology, has been 

 notified by the Aero Club of America of the 

 establishment of an award in the form of a 

 medal for the students at the institute. The 

 medal is to be termed the " Aeronautical Engi- 

 neers' Medal " and is for award annually for 

 merit to a student in the graduate course in 

 aeronautical engineering. 



At the University of Chicago Dr. Frank 

 Christian Becht has been appointed assistant 

 professor in the department of physiology, his 

 particular field of work being pharmacology. 

 Professor Becht, who is a graduate of the 

 University of Chicago, was for two years as- 

 sistant professor of physiology in the Uni- 

 versity of Illinois and later assistant pro- 

 fessor of pharmacology in the Northwestern 

 University Medical School. 



In the medical department of the Univer- 

 sity of Oregon Dr. J. M. ConnoUy has resigned 

 as professor of physiological chemistry and 

 Dr. H. D. Haskins, of Western Eeserve Uni- 

 versity, Cleveland, has been elected his suc- 

 cessor. Dr. B. L. Arms has resigned as pro- 

 fessor of bacteriology to accept a position in 

 the University of Texas and Dr. W. H. Nor- 

 ton, of Johns Hopkins Medical School, has 

 been appointed to the vacant position. 



Two professors from Louvain University — 

 MM. Charles Jean de Valee Poussin and Leon 

 Dupriez — ^have been invited by Harvard Uni- 

 versity to deliver lectures in the second sem- 

 ester. The former will lecture on mathematics, 

 the latter will give the Godkin lectures on 

 " Proportional Eepresentation in Belgium " 

 and two courses. 



DISCUSSION AND COBBESPONDENCE 



THE FUNDAMENTAL EQUATION OF MECHANICS 



In his recent review of Maurer's " Technical 

 Mechanics," ^ Professor L. M. Hoskins has 

 discussed at some length the question whether 

 P = ina or F/F' = a/a' is the better form in 

 which to introduce the " fundamental equa- 

 tion of mechanics." As Professor Hoskins' 

 defense of the equation F = ma is the clearest 

 I have seen, and as I am still one of those who 

 prefer the equation F/F' == a/a', I should like 

 to state here the advantages which this latter 

 equation seems to me to possess. 



In the first place, the qualitative notion of 

 force, and the use of the spring talance as an 

 instrument for the quantitative measurement 

 of forces, may safely be assumed to be familiar 

 to any one beginning the study of mechanics.^ 

 The first serious problem, then, which con- 

 fronts the teacher of dynamics is the problem 

 of making the student ujiderstand the effect 

 which a force produces when it acts on a 

 material particle. This effect is, of course, 

 the acceleration of the particle in the direc- 

 tion of the force, the exact quantitative rela- 

 tion being most simply stated as follows : 



If a given particle is acted on at two differ- 

 ent times hy two forces F and F' , and if a 



1 Science, December 4, 1914. 



2 The question of the unit of force, which oc- 

 cupies so large a place at the very beginning of 

 the subject in the ordinary treatment, need not be 

 dwelt upon at this stage. To the beginner, a 

 unit force is quite properly any force which brings 

 the pointer of a standard spring balance to the 

 point marked "1" on the scale, whether the in- 

 strument reads pounds, or dynes, or grams; just 

 as a degree of temperature is, to the beginner, 

 simply the distance between two divisions of the 

 scale of a standard thermometer, whether that 

 scale reads Fahrenheit, E6aumur or Centigrade. 

 The conversion factors connecting the various 

 degrees of temperature should indeed be stated; 

 but the question of ultimate standards, being 

 chiefly a question for the technician, need not be 

 raised at this point. For further details, see the 

 writer's " Eecommendations Concerning the Units 

 of Force, ' ' in the Bulletin of the Society for the 

 Promotion of Engineering Education, June, 1913, 

 the most important of which have already been 

 adopted by the U. S. Bureau of Standards. 



