2n\ 



Letters were read from Historical Society of Pennsyl- 

 vania ; J. P. Lesley of American Phil. Society ; N. S. Howe 

 of Haverhill ; A. E. Verrill of Norway, Me. ; W. F. Poole of 

 Boston ; W. P. Upham ; H. Curwen. 



Donations to the Library and Cabinet, were announced — 

 from Richard H. Wheatland ; N. J. Lord ; C. P. Preston, 

 Secretary of Essex Agricultural Society ; John S. Ives ; 

 James Upton ; C. B. Richardson of New York, N. Y. ; 

 Portland Society of Natural History ; S. M. Worcester ; 

 James A. Gillis ; Horace Brown ; Thomas H. Johnson ; 

 Henry M. Brooks ; George 0. Chase ; Stillman Barden of 

 Rockport ; Joseph Hammond. 



Rev. S. Barden of Rockport, being called upon by the 

 Chair, gave a very interesting and instructive account of 

 his researches among the quarries in Rockport. These 

 quarries have long possessed a great reputation for the 

 excellent building material furnished — specimens of which 

 may be seen in the principal cities of the Union. In 

 the extensive quarries worked by Eames & Co., can be 

 seen some of tlie best and purest granite in the country, 

 there is almost an entire absence of hornblende. Granite con- 

 tains quartz, feldspar and mica — sienite, quartz, feldspar and 

 hornblende ; frequently the four ingredients are found com- 

 bined together, viz. : quartz, feldspar, mica and hornblende ; 

 hence the rock of this region may be termed sienitic granite. 



These quarries exhibit numberless varieties in the color- 

 ing of the ingredients ; the quartz is shaded all the way 

 from a smoky color to a light watery hue, sometimes tinged 

 with red in a slight degree ; the feldspar of a half green 

 color ; the mica of an ebony black — occasionally some fine 

 atoms of the red oxide of manganese, and garnets are found 



