On the mutations of Geological nomenclature. 263 
we have no chalk. Whereas every part of the earth, yet 
explored, justifies our starting with the well known and 
universal rocks, granite and gneiss. 
The subdivision of alluvial formations into alluvial and 
diluvial is probably tenable. But shall we adopt these 
names ? It is said Vol. VII. p. 210, that, “* not one thou- 
sandth part of those tracts, marked as alluvial in this coun- 
try really belongs to that formation.” ‘That is, ifa modern 
writer choose to change the original and legitimate use of 
a word, this change renders all the previous applications 
of it improper. This is very extraordinary ; but still it 
does not equal a remarkable omission which we may al- 
most say characterizes American writers. I mean that of 
neglecting our own countrymen in order to do homage to 
Europeans. This same distinction in alluvial formations 
was suggested and enforced by our countryman, Mr. 
Schoolcraft, long before the suggestions of Buckland or 
Conybeare reached this country. Instead of restricting 
the word alluvial and thereby leaving no general term to 
express its original import, he uses the more appropriate 
terms primary and secondary alluvion. I published a 
short account of Mr. Schoolcraft’s views on this subject 
four years ago in the 2d, Ed. of the Index to the Becléey 
of the northern States. pp. 262—6. 
I have made these few enquiries and remarks with a 
view to invite discussion before such an entire revolution 
in the science is sanctioned in America. I would not be 
understood to imply that I will not follow these authors, as 
far as the geological structure of our country can be made 
to yield to their views. New names must be given, when new 
discoveries are made. Butsuch an entire and radica! 
change of classification is too great to be adopted, before 
our own rocks-and alluvial deposits have been extensively 
consulted. 
Most respectfully, 
Yours, 
Amos Eaton. 
Troy, (N. Y.) March 16, 1824. 
