PHILOSOPHICAL SOCIETY OF WASHINGTON. 183 



Medical and Surgical History of the War of the Rebellion, 1861-1865, Part II, 

 being the Second Surgical Volume. Washington, Government Printing 

 Office, 1876, 4to., pp. 1024. Second issue, 1877. 



Circular No. 9, War Department, Surgeon General's Office, March 1, 1877. 

 A Report to the Surgeon General on the Transport of Sick and Wounded 

 by Pack Animals. 4to., pp. 32. 



Report of a Board of Officers to decide on a Pattern of Ambulance Wagon for 

 Army Use. [Prepared by him as recorder of the board.] Washington, 

 Government Printing Office, 1878, 8vo., pp. 79. 



Contributions from the Army Medical Museum. Boston Medical and Surgical 

 Journal, Vol. XCVI, March, 1877, p. 361. 



Article Surgery in Johnson's New Universal Cyclopaedia. New York, A. J. 

 Johnson & Son, 1878, Vol. IV, pp. 1678-1686. 



Notes on Contributions to the Army Medical Museum by Civil Practitioners. 

 Boston Medical and Surgical Journal, Vol. XCVIII, February, 1878, p. 

 163. 



Recent Progress in Military Surgery. Same Vol., April, p. 531. 



Photographs of Surgical Cases and Specimens, taken at the Army Medical Mu- 

 seum, with Histories of three hundred and seventy-five cases. Washington, 

 Surgeon General's Office, 1866. 1881, 8 vols., 4to. 



The next communication was by Mr. Alexander Graham 

 Bell 



upon a modification of wheatstone's microphone and its 

 applicability to radiophonic researches. 



In August, 1880, I directed attention to the fact that thin disks 

 or diaphragms of various materials become sonorous when exposed 

 to the action of an intermittent beam of sunlight, and I stated my 

 belief that the sounds were due to molecular disturbances produced 

 in the substance composing the diaphragm.* Shortly afterwards 

 Lord Raleigh undertook a mathematical investigation of the subject, 

 and came to the conclusion that the audible effects were caused by 

 the bending of the plates under unequal heating.f This explana- 

 tion has recently been called in question by Mr. Preece,| who has 



*Amr. Ass. for Advancement of Science, Aug. 27, 1881. 

 f Nature, Vol. XXIII, p. 274. 

 % Roy. Soc, Mar. 10, 1881. 



