Wadsworth.] 
246 
[October 19, 
producing a perpetual cycle. Let the reader suppose all this and 
he will gain some idea of the principles and methods commonly 
employed in lithology as well as in a greater or less degree in 
chemistry as applied to rocks. 
This is no mere fancy sketch, but so far as can be done, by 
taking an illustration from a distinct science, shows some of the 
principles of lithology as taught to-day and some of the methods 
upon which rocks, even now , are classified. 
These principles and methods were utterly rejected by me in 
1878, which rejection was distinctly set forth in the abstract 
which Mr. Merrill criticised. Yet he demands that my work 
should conform to these very principles and methods! 
So far as the real weight of Mr. Merrill’s paper goes, the sub- 
ject might be dropped here, but owing to the implied charges 
and the importance of the subject, it is necessary to carry the 
discussion further in a manner somewhat personal to the present 
writer. The important question is this : shall the theories and 
classifications put forth by Messrs. King and Zirkel with so much 
confidence and sustained by the influence of the United States 
Geological Survey, as well as apparently by that of almost every 
scientist in the country, be longer accepted or not ? If correct 
they are to be accepted ; but if I am right, their acceptance places 
an incubus upon American lithology and geology that only long 
years can remove. 1 The importance is infinitely beyond that of 
any man or set of men. It is a question of some of the fun- 
damental truths of science. 
THE LITHOLOGICAL COLLECTION. 
When Prof. J. D. Whitney placed in my charge the lithological 
collections made by himself and by others in his employ, he stated 
to me that the rocks from California were in general the same as 
those collected by the Fortieth Parallel Survey, and described 
by Professor Zirkel. Professor Whitney expressed no dissent 
from the work of that survey, but on the contrary stated his 
belief that the arrangement and study would be simple and 
easy on account of Professor Zirkel’s work. 
1 It is to be remembered that Richthofen and King’s classification is not accepted in 
Europe and was not adopted by Zirkel until his visit to New York. 
