330 



Messrs. L. B. Stone and P. C. Hill were elected Resi- 

 dent Members. 



January 20, 1858. 



The President in the Chair. 



Mr. John Green exhibited a number of photographs, 

 taken by the collodion process, of microscopic objects, 

 many of which had been very highly magnified. In con- 

 nection with Mr. Albert Gould of the Scientific School, 

 he had been experimenting upon the subject, and had 

 succeeded in obtaining very fine and accurate represen- 

 tations of some of the fossil diatomacese, crystals, sec- 

 tions of bone, and various vegetable tissues. The most 

 transparent objects, such as fossil Naviculae, were well 

 taken, even when magnified eight hundred linear diam- 

 eters. 



Mr. C. H. Hitchcock exhibited a diagram of a geolog- 

 ical section from Greenfield to Charlemont, Mass., and 

 gave the following explanation of it : — 



This section was measured in October, 1857. The design of 

 it is to show tlie amount of erosion since the strata were brought 

 into their present position. 



I will enumerate the rocks in order, going from east to west, 

 beginning at Greenfield. At Greenfield we find the Connecticut 

 River Sandstone dipping 40 degrees E, Leaving the valley we 

 strike the Calcareomica-slate in Shelburne, having a dip of 67 

 degrees E. This rock consists of micaceous slates and schists 

 interstratified with bluish-gray silicious limestone. The dip 

 gradually increases to 38 degrees E. at two and a third miles 

 from the commencement of the rock ; when, upon East Moun- 



