Localities of Minerals. 241 



contrasted with the white, stony matrix, (principally quartz 

 and sulphat of barytes) in which it is enveloped, it forms ele- 

 gant specimens. 



Scintillating Limestone. — In Vermont, a singular scintillating 

 limestone is found, of which an account is given in the follow- 

 ing extract of a letter from Mr. George Chase, dated Ran- 

 dolph, February 19, 1818. 



*' The object of the present letter is to acquaint you with a 

 circumstance relating to the limestone that abounds in this pri- 

 mitive country, which to me is inexplicable. This carbonate 

 of lime is of a pale sky-blue colour ; effervesces strongly with 

 nitric acid ; and, by burning, produces lime, so that there is 

 no question as to the identity of the mineral. But it likewise 

 gives forth sparks with steel : — this I concluded, at first, to be 

 an accidental circumstance ; but every specimen that I have 

 tried, from various quarters of the country, uniformly gives 

 fire with steel. The limestone is found in layers, in blocks, 

 and masses, disseminated among the clay-slate that covers the 

 greatest part of the townships in this vicinity. When first 

 taken from the earth, and exposed to the air, it is covered with 

 an incrustation of a dark reddish-brown colour, that crumbles 

 easily between the fingers, and is generally from one inch to a 

 foot in thickness. This incrustation, however, hardens on a 

 long exposure to the air. This led me to think that the in- 

 crustation was owing to the decomposition of the limestone, 

 which was produced by the sulphuret of iron, intimately dis- 

 seminated through the rock, which would also explain the sin- 

 gular circumstance of its striking fire. But on dissolving a 

 small quantity of the mineral in nitric acid, and adding a drop 

 or two of the decoction of gallnut, no discolouring of the 

 liquor was produced." 



Limpid Quartz. — West Canada Creek, a northern branch 

 of the Mohawk, affords, in its sands, small crystals of quartz, 

 limpid, and terminated at both ends by pyramids of six sides ; 

 we are indebted for specimens to Professor Fisher. 



Fetid Primitive Limestone, ^c. — From the vicinity of Wil- 

 liamstown College, through the kindness of Professor Dewey, wc 



Vol. I.. ..No. 3. 20 



