342 



Silica 



Magnesia . 

 Protoxide of Iron 

 Oxide of Chromium 

 Water 



42.97 



41.96 



2.48 



0.87 



12.02 



100.30 

 and the composition of massive Serpentine is nearly the same. 



He admitted that there are numerous veins of magnesite, as 

 well as of dolomite spar, or magnesian carbonate of lime, in the 

 Koxbury, Vermont, Serpentine Marble, but did not consider the 

 Serpentine itself as composed of carbonate of magnesia in the 

 place of hydrous silicate of magnesia. 



He had, as the original surveyor of the quarries, and the first 

 who published on the subject of that marble, named it Vennont 

 Verd Antique, on account of its close resemblance to the cele- 

 brated Verd Antique existing among the ancient monuments of 

 Home. He believed this name to be quite appropriate, and it 

 has been adopted by the Company. 



The analyses which he read at the last meeting of the Society, 

 justified, he believed, this conclusion, and the name will therefore 

 be retained. ' 



His analysis of the Lynnfield Serpentine was made on the 

 27th of May, 1837 ; the specimens having been taken from the 

 quarry by himself, while employed by the owners of it. 



He found it readily soluble in sulphuric acid, and he made 

 from 100 grains of it, 127 grains of anhydrous sulphate of mag- 

 nesia, or 178 grains of crystallized Epsom salts, and then recom- 

 mended the manufacture of that salt from it, as was subsequently 

 done in Koxbury. 



On the 6th of August, 1839, Dr. Jackson completed his analy- 

 ses of the Serpentine Marbles of Proctorsville, Vermont, and 

 subsequently, in the spring of 1840, surveyed the quarries from 

 .which the marble was obtained. 



In 1853, he made the first examinations of the Serpentine 

 ledges of Roxbury, Vermont, and directed the owners of them 

 as to the most suitable localities for quarrying the marble, and 

 he had since revisited them and given further directions. In 

 December, 1854, at the request of the company, he made bis 



