260 Dr. J. W. Webster on St. Michael 
felspar is divided into prismatic distinct connections, which 
are from half an inch to two inches in length, and from an 
kn 
eighth of an inch to an inch in thickness.” The angles and ~ 
edges of these masses were rounded and showed marks of 
attrition—Angular spaces have been left between the con- 
cretions, in one of which, says Dr. Webster, T discovered a 
portion of transparent quartz having a red tint. ‘The spaces 
are partially filled by crystals of hornblende projecting into 
fels + sg 
ost singular circumstance in these masses, is the 
division ‘of each one of them into a coarse and fine grained 
—— he latter, composed likewise of hornblende and 
sue intimately mixed, and in nearly equal a 
forms a nucleus, which is completely enveloped by t 
lucency of the foliose, in all these fragments, is such as 
evinces that they could not have been subjected to a very 
elevated temperature.” The author then goes on to re- 
mark, that “ if these rocks had been found on a mountain, 
composed of the primitive rocks of many geologists aes 
would have been described as granite, or sienite, and ther 
is in Dr. Webster’s opinion, no reasonwhy they are oh 
in their present situation, equally entitled to the name.” 
Perhaps we donot exactly apprehend the author’s meaning. 
He evidently does not intend that the specimens resembling 
granite and sienite (and this resemblance has ap ared to 
us on inspection of the specimens to be very striking indicate 
that the immediate region in which they are found is primi- 
tive, for this is disproved by the whole tenor of his observa- 
tions: If he means nothing more than that the pieces in 
question have such indicia as prove their origin from prim 
tive rocks, this conclusion contains nothing improbable 
for fragments of primitive rocks are not uncommon among 
~ voleanic ruins; and the mechanical analysis of lava by Cor 
dier, is said to discover principally primitive minerals. We 
