Intelligence and Miscellanies. 189 
green tourmaline, indicolite, and siliceous feldspar, three miles 
north west from the center of the town, on the farm of Mr. 
Stearns. I have found only a single crystal, which I ob- 
tained several years ago, in the granite containing the above 
minerals: but [ did not examine it till lately. A recent visit 
interesting metal: For in Cornwall “it is generally in the 
vicinity of a vein of tin ore, that disseminated grains of tin- 
stone are found in the rock. 
he specimen which I found consists of a single crystal, 
weighing about fifty grains: or rather of a portion of one 
large crystal, with parts of several smaller ones, projecting 
from it hemi-tropically. e form is evidently an octahe- 
dron, with a square base; but its angles, as measured with a 
common goniometer, differ several degrees from the meas- 
urements of the primary form of tinstone, as given by W. 
Phillips. His results (making use of Brooke’s notation) are, 
P2183° 36 
Pon P” 67*52 
That from Goshen gives 
P on P' 125° 
Whence this discrepancy arises I am unable to say. 
would suggest, however, that it is not impossible, that I have 
mistaken the true form of the crystal; as only a few of its 
faces are exhibited in perfection. 
sto the external characters of this mineral, it will be suf- 
ficient to say, in general, that they correspond almost exactly 
with the oxide of tin from Cornwall and Bohemia. Its: spe- 
cific gravity is 7.14. 
n charcoal it was readily reduced before the oxy-hydro- 
gen blow pipe, without decrepitation; and after reduction, 
it burnt with the brilliant white light of tin. Tinstone from 
Bohemia was not reduced so easily. 
n order to ascertain whether the reduced globule would - 
give the crackling sound, so striking in metallic tin, I placed 
