1883.] 339 [Annual Meeting. 



General Meeting, April 18, 1883. 



Vice-President, Mr. F. W. Putnam, in the chair. Nineteen per- 

 sons present. 



Mr. Wm. M. Davis read a paper on the causation of gorges 

 and waterfalls in glaciated regions. Mr. Davis also spoke of the 

 results of an excursion to Becrafts Mountain, on the Hudson. The 

 Helderberg limestones were supposed to overlie unconformably 

 the older sandstones, although the evidence was unsatisfactory and 

 not nearly as clear as would be supposed from the diagram given 

 by Mather, in 1843, in the Geology of New York. 



Annual Meeting, May 2, 1883. 



The President, Mr. S. H. Scudder, in the chair. Thirty per- 

 sons present. 



The following reports were presented : — 



Report of Alpheus Hyatt, Curator. 



It was rightfully imagined when the present plan of arrange- 

 ment was adopted, that the greatest obstacle in the path of any 

 attempt to show the natural relations of the products of the earth 

 would be the department of Mineralogy. It has been found, 

 however, that though the separation of minerals from the mother 

 rocks on account of their purer composition and definite forms, is 

 artificial, still this separation has its logical uses. 



It enables us to explain with directness and precision the rela- 

 tions of all the elements, and their strictly inorganic compounds, 

 and prepares the mind for the consideration of the more compli- 

 cated aspects of the Geological and Biological collections. Miner- 

 alogy acts as the vehicle for the conveyance of all the preparatory 

 facts in Physics and Chemistry, which are essential for our pur- 

 poses. 



While we cannot find such definite marks of gradations in 

 minerals as among animals and plants there are in nearly every 

 division of minerals, even with their present entirely artificial and 

 probably unnatural classification, such distinctions as those of 

 Anhydrous and Hydrous groups, the simple Sulphides and double 



