PROCEEDINGS. 



Eight hundred and fifty-first Meeting. 



May 24, 1892. — Annual Meeting. 



The President in the chair. 



A quorum was not present and it was 

 Voted, To meet on adjournment on Wednesday the 15th of 

 June. 



The Report of the Council was read. 



The Treasurer and the Librarian presented their annual 

 reports. 



The following papers were presented by title : — 

 Note on Orthogonal Matrices. By Henry Taber. 



On the least Number of Vibrations necessary to de- 

 termine Pitch. By Charles R. Cross and Margaret E. 

 Maltby. 



On some Experiments with the Phonograph, relating to 

 the Vowel Theory of Helmholtz. By Charles R. Cross and 

 George E. Wendell. 



An Investigation of the Excursion of the Diaphragm of a 

 Telephone Receiver. By Charles R. Cross and Arthur M. 

 Mansfield. 



New Pluenogams collected in New Mexico by C. G. Pringle 

 in 1890 and 1891. By Benjamin L. Robinson. 



