Notice of the Ancram Lead Mine. 247 
the tuff, the imbedded sandstone masses in that rock must 
have proceeded. And this is one of those cases in geology, 
in which it is demonstrable, that a long interval must have 
elapsed between the formation of different beds of the same 
rock. In this instance, it is certain, that the lower beds of 
the slate and greenstone must have been first arranged and 
consolidated ; and then, some violent convulsion must have 
taken place, in which water, no doubt, was the principal 
agent, and by which, the slate and the greenstone were 
abraded and the detached masses round them : the process 
must have been reversed, and the tuff cemented and con- 
solidated ; and finally, the agents employed must have been 
brought to the same state as when the lower beds of slate 
were deposited, in order to the production of the same 
slate above the tuff. Such a remarkable series of revolu- 
tions must have demanded a considerable length of time. 
I have no leisure, nor disposition, to discuss the bearing of 
these facts upon existing geclogical systems ; nor to point 
out their important relation to the first chapter of Genesis. 
1 know of no facts in the geology of our country, that show 
so irrefragably, that long periods of time must have been 
occupied in the formation of the secondary rocks. 
E. H. 
P. S. Upon further examination, [ am inclined to refer 
ihe comglomerate rock described above, to the Conglom- 
erate Quartz Rock of MacCulloch, as described in his geology 
of the Western Isles, and in the London Geological Trans- 
actions, Vol. 1. p. 60. Second Series. 
fl 
Arr. VIII.—Notice of the Ancram Lead Mine, by Cuaruzs 
A. Ler. 
To tHE EpiTor. 
I waTELY visited the lead mine at Ancram, Columbia 
County, N. Y. and as I have seen no notice of this locality 
in the Journal of Science and Arts, the following particulars 
may not perhaps be wholly uninteresting. 
In passing from Salisbury to Ancram, we first meet with 
alternations of Gran. V.imestone and Mica Slate and the 
