240 



nated abruptly. There appeared to take place in the nervous expan- 

 sions of the organs of sense, a process resembling that of attention, 

 as exhibited in the operations of the brain ; and this was frequently 

 the cause why our perceptions were at one time so much keener than 

 at others. 



Dr. Patterson exhibited to the Society a second diamond 

 from Hall County, Georgia, nearly three carats in weight, and 

 considered to be of the first water. Mr. Peale stated that he 

 had a specimen of granular quartz, supposed to be the gang of 

 the diamond, that was decidedly flexible. 



Stated Meeting, March 6. 



Present, sixteen members. 



Dr. Patterson, Vice-President, in the Chair. 



A letter was read from the New York Historical Society, 

 dated New York, February 26, 1846, in relation to the print- 

 ing, by Congress, of only one hundred copies of the Memoirs 

 on Subjects of Science, prepared by gentlemen of the United 

 States Exploring Expedition, and it was referred to the Com- 

 mittee appointed on the same subject at the last meeting. 



The following donations were announced : — 



rOR THE LIBRARY. 



Journal of the Franklin Institute of the State of Pennsylvania. Third 

 Series. Vol. XI. Feb. 1846. No. 2. 8yo.— From Dr. Pat- 

 terson. 



The Medical News and Library. Vol. IV. March, 1846. No. 

 39. 8vo. — From Messrs. Lea <^ Blanchard. 



Annual Report of the Directors and Physicians of the Kentucky Lu- 

 natic Asylum to the Legislature. December Session, 1845. 

 Frankfort, Ky. 1846. 8vo. — From the Kentucky Historical 

 Society. 



Report from the Secretary of the Treasury, communicating a Report 

 of the Superintendent of the Coast Survey, showing the progress 



