291 



iSonie letters received from the Department of the Inte- 

 I'ior ; R. Damon of Weymoiitli, England; and from others 

 were noticed. 



The chair briefly reviewed the origin, progress and modi- 

 fications of the field meetings since their first experiment ; 

 gave a short history of the Essex Institnte, — nrged the co- 

 operation of friends of science and civil progress in the 

 county to carry out the designs contemplated in its organ- 

 ization. 



B. F. Mudge of Lynn, gave some account of his geologi- 

 cal investigations to-day. He exhibited some pieces of fel- 

 spar, which he had found during his walk from the rail- 

 road station ; and he alluded to some of its uses in the arts ; 

 for instance in porcelain manufacture ; in making artificial 

 teeth, <fec. He had also visited the serpentine quarry this 

 forenoon, which some twen.ty years ago had been worked for 

 the manufacture of Epsom salts. The mine is only a small 

 portion of a ledge of the mineral, which outcropping through 

 the drift shows itself in several places in the A'icinity. The 

 serpentine is pure and with facilities of cheap labor, it might 

 be profitable in the making of Magnesia and Espom salts. 

 The mineral, he said, was more pure than that of Newbury, 

 at the Devil's Den, visited not long since by the Institute ; 

 but for verd antique marble, it would not prove to be so 

 beautiful: an elegant specimen of this particular variety 

 was to be seen in the pedestal of the new Franklin Statue, 

 in Boston, and which was quarried in Roxbury, Vermont. 

 The beauty of serpentine as verd antique marble consists in 

 the mixture of white limestone, which diminishes its purity 

 as a mineral just in proportion as its white, wavy lines pre- 

 dominate. Dr. Charles T. Jackson examined this quarry 

 in 1837, and pronounced it to be verd antique of various 

 shades of green, from the darkest olive to grass green. He 

 found it to form an enormous bed, running in a north-east 

 by north, south-west by south direction, and appearing to dip 

 to the north west about 45°. The soil covers the rocks which 



