Foreign Notices in Mineralogy, &c. 243 
the red sandstone and conglomerate, disrupting the rock in 
a narrow dyke: no possible supposition of aqueous agency 
could have caused this appearance. 2 WADE 3 
Look at the same volume, p- 134, for the localities of a- 
gate, Chalcedony, Zeolyte, Titanium, Prehnite, &c. they 
amount to proofs of the volcanic character of the country 
from Deerfield to East-Haven and Woodbury :* for all these 
substances are thus found as the indubitable accompany - 
ments of rocks whose igneous origin is undisputed (Iceland, 
Ferro, &c.) and are never thus found in rocks of undisputed 
aqueous origin. T 
. Since writing the above, Ihave been induced to 
consides as the source of volcanic fire, the caloric of tem- 
perature given out by the condensation of a column of at- 
mospheric air, reaching from the surface below the old 
Granite. On the same principle as the common condensing 
tube for firing punk. It appears that the temperature of 
mines increases about 12 or 14° of Fahrenheit Spry is at 
the depth of one thousand feet. ave not yet had tim 
- give sufficient consideration to the subject, to state any ra- 
o of compression thothes than Cotes’s) or the quantum of 
et een Caloric by the condensation of the lowest part 
of the column. I iota throw out the idea only for con- 
sideration. :¥ 
Arr. I1.—Foretgn Notices in Mineralogy, Geology, ancient 
Arts, &c.; communicated by Dr. J. W. Wesster. 
Boston, Nov. 25th, 1821. 
To Pror. Situiman, 
Dear Sir, 
From Thomson’s Annals of Philosophy, I extract the 
seal of an analysis of a substance that occurs in the Lime- 
shee of Pargas, (by P. A. V. Bondsdorf, Ph. ibe, of Abo.) 
bos. 3; it was ii considered Tremolite—it is peer 
3 eona 
seniataa hh: LE +. 22 
rated. ., many m iles of primitive from the great trap region of New- 
England. Vid. Vol. II. pa. 231 of Sia dnceeiiec Ep. 
