92 TRANSACTIONS OF THE [xov. 20, 
1868, 658) are probably of the same general form of origin with 
the zine ores. It is significant that they lack sulphur entirely. 
7. It may occur to some that the metals have been dissemin- 
ated through the limestone and have been segregated or concen- 
trated along the ore horizon by the oft mentioned tendency of 
ore thus to collect together. The possibility of such a process 
cannot well be denied, although it seems to the writer far less 
likely than one on which special confidence is here placed. It 
would require an enormous extent of wall rock to yield the 
amount of ore here visible, and the migration of material 
through a great amount of rock favorable to its precipitation. 
8. The ore bodies have been said to be analogous to the 
ordinary magnetite in the gneisses of New Jersey. This throws 
very little if any light on the method of origin. 
9. Some additional probability is given to the reference of 
the ores to the stimulating action of the granite, because refined 
analysis of the zinc-white reveals the presence of small traces of 
tin, as well as other metals. ‘Tin is a characteristic associate of 
granite. 
In this instance, as so often in the case of ore deposits, we are 
unable to go beyond the fixing of the most probable cause 
of formation, but bearing in mind the above points, in the state- 
ment of which the attempt has been made to be as fair and 
judicial as possible, the following outline of the process may be 
traced : 
The ores were most probably deposited from solutions, set in 
circulation by the intrusive rocks. These solutions spread 
through a particular bed, as along a particular set of bedding 
planes in each locality, replacing and impregnating the walls 
with ore. The kind of minerals which were first deposited is 
obscure. We would expect sulphides, but can find no trace 
of them. ‘The present character of ore is probably in no small 
degree the result of metamorphism. After deposition, walls 
and ore were folded by mountain-making pressure, operating 
along a northwest and southeast line and metamorphosed. An 
unknown but doubtless considerable amount was eroded. At 
some period subsequent to the folding, the great trap dike of 
the Buckwheat Mine was intruded, and since then there seems 
to have been slight, if any, disturbance. 
THe MINERALOGY. 
The mineralogy of this limited region is almost synonymous 
with the mineralogy of the State, and its contributions of new 
species to the science are not few. The locality became well 
known at the beginning of the century, and has been a prolific 
