. , i by 
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 Moshassue 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 afforded 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. i te . 
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 am 
cient Wigwam. - : ms 
“ Warwick neck is entirely underlaid by the rocks belonging git 
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 Natie, there ate 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 counly 
Mass. One of these rocks weighs 64 tons, answering to 600 eubie 
feet, being 15 feet long, 10 feet wide, and 4 feet thick. The wil 
mineral is a silicate of alumina and protoxide of iron, plus silicate of 
manganese, plus water—or water 4, silex 33.2, alumina 29 magnes!® 
‘24, protoxide of iron 25.93, oxide of manganese 6. 
7 * In honor of Mr. Owen Mason, of Providence. 
