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INTRODUCTION. 
Some geologists imagine that the order of creation 
is registered in the rocks which compose the external 
crust of the earth, and that they can there clearly read 
a progressive development of organic life; in other 
words, that a succession of more perfect animals may 
be traced in ascending from the lower strata to the 
upper or more recent formations; that there is a gra- 
dual approach to the present system of things, and a 
succession of destructions and creations; worlds of’ 
living beings alternating with worlds of desolation 
and death, antecedent to the existence of man. 
Others, again, contend that there is often a wide 
and palpable discrepancy between the nature of the 
rock, and the fossiis which it contains, and, therefore, 
that such inquiries afford no clue, whatever, to the 
order of creation.* We propose not to enter the field 
* Nothing can be more opposed to true science, than to pro- 
nounce on the priority of formation, or the comparative age of 
rocks, from either their structure, or the organic remains they 
present. M. Alexandre Brongniart thus propounds his opinion: 
*¢In those cases where characters derived from the nature of the 
rocks are opposed to those which we derive from organic re- 
mains, | should give the preponderance to the latter.”’ This 
seems to us to imply an admission, that nothing definite can be 
inferred from the nature of the-rocks; moreover, that between 
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