264 



The Treasurer, Mr. Pease, presented his annual report, 

 showing a balance due to him of §19. On motion the re- 

 port was referred to a committee for examination. The 

 committee appointed consisted of Dr. Hough and Mr. Pat- 

 erson. 



Prof. Perkins gave a new and beautiful solution of the 

 problem of fifteen girls at boarding school being required 

 to walk out in rows of three each day, the components of 

 each three being different each day. His method consisted 

 in making any desirable primitive arrangement, and from 

 this deducing by regular succession the only possible re- 

 maining arrangements. Prof. Perkins said that he did not 

 assume to determine the number of primitive arrangements, 

 but with any given primitive arrangement, seven other 

 arrangements might be obtained by his method ; the eighth 

 arrangement that would be obtained by pursuing the same 

 rule would be a return to the first. 



Adjourned. 



February 1, 1859. 



The Institute met according to adjournment ; present, 

 Messrs. Carpenter, Carroll, Edwards, Gould, Hall, Homes, 

 Luther, Minor, Munsell, Murray, Paterson, Pease, Swan, 

 Taylor and Yan Santvoord. 



Mr. Homes was called to the chair. 



Under proposition of members, R. H. Bingham was pro- 

 posed as a resident member of the Institute. 



Prof. Hall gave a description of a new genus Brachio- 

 poda, which he had discovered among the fossils which 

 he had collected in the Helderberg mountains. He showed 

 by means of diagrams and specimens the points of difference 

 between it and the genus with which it had usually been 

 confounded. 



Prof. Hall then proceeded to speak of the economical 

 products of geology, especially as regards the materials of 

 building and ornamenting edifices. He pointed out that 



