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gate and distinguish the separate layers and rocks which form the rind 
or crust of our globe. I say rind or crust, because, if all the sepa- 
rate layers, from the newest or most recently formed, down to that 
which appears to be the oldest, were placed one over the other in 
complete order, their total thickness would not exceed twenty miles, 
and as our globe is roughly calculated as being eight thousand miles 
in diameter, we are left in complete ignorance of the nature of 
the intervening space of seven thousand nine hundred and sixty 
miles. But it may be naturally asked, how is it that we get this 
knowledge of nearly twenty miles, when our means of penetra- 
tion by boring or mining, has in no instance been so much as one 
mile. Fortunately for the student, internal disturbances have 
caused the separate layers to be tilted up, so as to bring the oldest 
beds within reach of study, and to form, in many instances, our 
highest mountains; and though the separate layers may not be 
found lying in regular order, one over the other, the newer often 
being found resting on beds of much older date, the interveniug 
beds being absent, the missing beds are found in other places rest- 
ing conformably on those immediately below them, and thus supply 
the missing links and enable the geologist to obtain a considerable 
insight of the disposition of land and water in former times. It is 
therefore the duty of the student in geology, to learn to distinguish 
the several layers by their lithological and mineralogical characters, 
and especially by the fossil remains found therein. Apart from the 
interesting nature of the study, little need be said of its great im- 
portance and value, as enabling the geologist to state with some 
degree of precision, the probabilities of obtaining coal and other 
minerals, and thus preventing the waste of money in futile search. 
The various characters exhibited by the different rocks and layers 
of earth which formed the hills and valleys, the cliffs and rocks of 
the river margin and the sea shore, could not fail to attract the 
ancient philosopher, and the occurrence of shells and other marine 
remains in places far removed and elevated above existing rivers 
and seas, must have still further formed subjects for speculation 
and thought, and hence from tne earliest time various theories have 
been propounded to account for such peculiarities and anomalies. 
Tradition, from a very early period, has handed down a reference to 
some great cataclysm in form of a great irruption of water over a 
large inhabited district, which from the limited knowledge of the 
people, who in all probability emigrated, and the natural distortion 
of tradition or oral communication became exaggerated into a uni- 
versal deluge. We find the Hindoos, Chaldeans, Assyrians, and 
Egyptians, make reference to a deluge; and it was but natural that 
Moses, who passed the early part of his life among the Egyptians, 
should in writing his account of the creation and the early history 
of the Jews, introduce the account of the deluge. This Mosaic 
account of the creation and the after deluge, has been a sad 
