INTRODUCTION. 
81 
elusions, I have chosen in this place to go through with the preliminary 
description of the several formations, their character and geographical 
distribution, in order that the student may have before him an example 
upon which I would found my general propositions. I do this also since 
it has been from the actual study of this series of strata in their accu¬ 
mulation and distribution, that I have arrived at the results here 
given. These conclusions, moreover, have been deduced by studying the 
rocks, and the phenomena attending them, entirely independent of the 
theoretical views advanced by other authors. I have necessarily in¬ 
corporated the general philosophic views so long ago clearly set forth 
by Babbage, Herschel, Lyell and others; since these had early been 
fixed in my mind as a part of the elements and principles of geological 
science. In this preliminary paper I have not thought it necessary to 
enter into any special discussion of the structure of the Appalachian 
range, and its analogy with other mountain ranges. Had this subject 
come within the scope of this notice, I should not have been unmind¬ 
ful of the labors of European and American geologists in this field of 
investigation. In rocks of the same age in Great Britain, we have the 
results of the admirable researches of Sedgwick and Murchison ; and 
among those who have investigated the question either in regard to 
the laws governing this structure, or in the application of these laws 
to the elucidation of structure in particular regions, may be named 
Sir James Hall, Sir Henry de la Beche, Hopkins, Martin, Fitton, Wea¬ 
ver, Dumont, Studer and others ; while in our own country the same 
subject has been more fully discussed under a new aspect, by Profes¬ 
sors W. B. and H. D. Bogers. 
My constant devotion for more than twelve years to another de¬ 
partment, requiring a great amount of detail and technicality, and 
the constant dealing with minutiae, has left me little time for the cul¬ 
tivation of the higher problems of the science; and I must confess 
myself, moreover, greatly in arrear, regarding the present aspect of 
these and similar points of discussion. 
[ Palaeontology III.] 11 
