Ix Trains. Acad. Sci. of St, Louis. 



Jux\E 4, 1900. 



President Engler in the chair, sixteen persons present. 



Dr. Warren B. Outten addressed the Academy on the true 

 interpretation of sound, presenting what he believed to be a 

 new principle in acoustics, and describing a method of 

 re- enforcing sounds by means of various membranes. 



Two persons were proposed for active membership. 



October 15, 1900. 



President Engler in the chair, sixteen persons present. 



The addition of the Department of Zoology of the Univer- 

 sity of Nebraska, and Naturae Novitates, of Berlin, to the 

 exchange list of the Academy was reported by the Council. 



The Secretary laid before the Academy a portion of a 

 femur [supposed to be that of a bison], presented by Mr. 

 E. A. Hermann, Sewer Commissioner of the city, who 

 reported that it had been found in a four-foot gravel seam 

 under twenty- two feet of clay, in the excavation now being 

 made for the Tower Grove storm sewer, between the Frisco 

 and Missouri Pacific railways, 1,934 feet east of King's High- 

 way. On motion, the thanks of the Academy were extended 

 to Mr. Hermann for this addition to the Academy's collec- 

 tions. 



Mr. William H. Koever discussed the subject of the estab- 

 lishment of the method of least squares, in an exhaustive and 

 masterful manner which does not admit of brief abstract. 



A paper by Professor F. E. Nipher, entitled Positive pho- 

 tography, with special reference to eclipse work, and a paper 

 by the same author, entitled The frictional effect of railway 

 trains upon the air, were presented and read by title. 



Mr. C. F. Baker exhibited a collection which he had pre- 

 pared for the National Museum, representing nearly all of 

 the species of fleas thus far known to science. 



Dr. Hartwell N. Lyon, of St. Louis, Professor John M. 

 Holzinger, of Winona, Minnesota, Mr. Ambrose Mueller, of 

 Webster Groves, Missouri, and Mr. Julien Reverchon, of 

 Dallas, Texas, were elected to active membership. 



Four persons were proposed for active membership. 



