186 Bibliography. 



Much limestone is burned in Smithfield ; the kilns contain 500 casks 

 of lime, and by the wearing away of the walls they become so large 

 as to contain 550 or 600 casks, which are worth about 1300 dollars. 

 The calcined lime is very nearly as bulky as the limestone, and is said 

 to lose only one third of its weight in burning, instead of 44 per cent, 

 of carbonic acid, which it contains if pure. The lime made from the 

 magnesian or hard variety is preferred by masons, as the mortar har- 

 dens sooner than if made of pure lime, as the magnesia renders it 

 somewhat hydraulic. Dr. Jackson is of the opinion that lime, prop- 

 erly burned by anthracite, is equal in whiteness and strength to that 

 burned by wood. The kilns connected with the Dexter rock have 

 been wrought for more than eighty years, and during the last forty 

 they have produced not less than 10,000 casks per annum. 



The mineral called rhomb spar is said by our author to be errone- 

 ously named, for it is not a magnesian carbonate of lime, but contains 

 a considerable proportion of carbonate of manganese. 



On Moshassuc stream, there is a bed of soapstone or talcose rock, 

 twelve feet wide, included between walls of chlorite slate; it is very 

 useful as a lining to the lime kilns. 



On page 70 of the report there is a section exhibiting, very palpably, 

 the passage of a conglomerate into a mica slate, the fine grained va- 

 rieties of which have aflforded from 5 to 17,000 dozen whetstones an- 

 nually — the last year 10,000 dozen, or 120,000 stones. 



The beautiful crystals of amethyst formerly found near Bristol ferry, 

 are exhausted. 



Mount Hope, the seat of the celebrated Indian warrior Philip, king 

 of the Pequots, is 193.6 feet high : it is composed of granite and 

 quartz, and a clear spring of water still flows near the site of the an- 

 cient wigwam. 



" Warwick neck is entirely underlaid by the rocks belonging to 

 the Rhode Island coal formation, the fine grained graywacke and the 

 carbonaceous clay-slates, charged with numerous impressions of fos- 

 sil plants and with narrow seams of anthracite and plumbago." The 

 upper surface is here tertiary. 



In the town of Natic, there are bowlders containing a new mineral, 

 which Dr. Jackson has called Masonite.* There are no similar rocks 

 in place nearer than the town of Ward, in Worcester county, 

 Mass. One of these rocks weighs 64 tons, answering to 600 cubic 

 feet, being 15 feet long, 10 feet wide, and 4 feet thick. The new 

 mineral is a silicate of alumina and protoxide of iron, plus silicate of 

 manganese, plus water — or water 4, silex 33.2, alumina 29, magnesia 

 .24, protoxide of iron 25.93, oxide of manganese 6. 



In honor of Mr. Owen Mason, of Providence, 



