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. VIJ. p. 210, that, “‘ not one thou- 
Europeans. This same distinction in alluvial formations 
was suggested and enforced by our countryman, Mr. 
Schoolcraft, long before the suggestions of Buckland or 
Jonybeare 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 
ern } 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 Geo ogy 
ofthe northern States. pp. 262—6. ; 
I have made these few enquirics 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 | will not follow these authors, as 
far as the geological structure of our country can be made 
to yield to their views. ‘names must be given, when new 
iscoveries are made. Butsuch an entire and radical 
change of classification is too great to be adopted, before 
ur own rocks and alluvial deposits have been extensively 
consulted, ‘ 
@ 
Most respectfully, 
~ Yours, s 
Amos Eaton. 
Troy, (N. ¥.) March 16, 1824. 
