136 proceedings: philosophical society 



at a former meeting of the Society, when the principle of dimensional 

 homogeneity was assumed and used as a starting point. The paper 

 was discussed by Messrs. Hansen, Agnew, and Douglas. 



The 747th meeting was held on December 5, 1914, at the Cosmos 

 Club, President Fischer in the chair; 70 persons present. 



By invitation, Prof. W. S. Franklin, of Lehigh University, ad- 

 dressed the Society on Some 'phenomena of fluid motion and the curved 

 flight of a baseball. The steady curvature of path of a rapidly spin- 

 ning baseball was explained on the basis of the principle enunciated 

 by Daniel Bernoulli in 1726, viz., in a stream of water, or air, the 

 pressure is high where the velocity is low, and the pressure is low where 

 the velocity is high. The principle and its apphcation in fluid motion 

 were illustrated both by lantern slide diagrams and experiments. The 

 "spit-ball" was also explained by the same principle. In the course of 

 the lecture the speaker, in an interesting digression, raised question as 

 to the strict validity of the law of cause and effect. The paper was 

 discussed by Mr. Wiley, who cited several phenomena in his own 

 experience during wind storms that could be explained by Bernoulli's 

 principle, and by Mr. Humphreys, who asked as to the explanation 

 of the principle. Professor Franklin then discussed some of the limi- 

 tations of the principle. The best point of view in explanation is that 

 of conservation of energy. 



The chair expressed to the speaker the thanks of the members and 

 guests for his interesting lecture and experiments. 



The 748th meeting (44th annual meeting) was held on December 

 19, 1914, at the Cosmos Club, President Fischer in the chair; 24 

 persons present. 



The report of the secretaries was read by Mr. Agnew, showing an 

 active membership of 144. Sixteen regular meetings have been held. 

 The report was ordered accepted. The Treasurer's report, dated De- 

 cember 16, 1914, was read by Mr. Sosman. The total receipts for the 

 year were $3078.77, including proceeds from sales of investments; 

 total expenditures, .$3151.20, including purchases of bonds of par 

 value $2500; total investments, $11,500; cash in hand, $454.72. The 

 report was ordered accepted. The report of the Auditing Committee, 

 consisting of Messrs. White, Kimball, and Ferner, was read by 

 Mr. White. This Committee reported the statements in the Treas- 

 urer's report to be correct. The report was ordered accepted. It 

 was moved and passed that the reading of names of members entitled 

 to vote be omitted. Messrs. F. J. Bates and C. A. Briggs were 

 appointed tellers. The following officers were dul}^ elected for the 

 ensuing year: President, W. S. Eichelberger; Vice-Presidents, L. J. 

 Briggs, Wm. Bowie, G. K. Burgess, and W. J. Humphreys; Secre- 

 taries, J. A. Fleming and P. G. Agnew^; Treasurer, R. B. Sosman; 

 General Committee, N. E, Dorsey, E. Buckingham, M. D. Hersey, 

 E. G. Fischer, R. L. Paris, H. L. Curtis, D. L. Hazard, R. A. 

 Harris, W. P. White. It was moved and carried that the Secretary ' 



