420 Postsc7'ipt. 



proved, and I will immediately cause a resurvey of the state to be 

 made by other scientific gentlemen. 



S. Van Rensselaer. 



Albany, June 22d, 1831. 



Remarks. — Although we have not always agreed in opinion with 

 our correspondents, and with Prof. Eaton among the rest, we have 

 been satisfied that his valuable labors have contributed very materially 

 to the advancement of geological knowledge in this country, by pro- 

 moting investigation, and adding largely to the mass of facts, which 

 constitute the true riches of geology. Were the entire crust of the 

 planet fully explored, and the nature and order of its mineral masses, 

 and their contents accurately ascertained, described, and laid down 

 in maps and sections, no one would hesitate to say, that a vast ser- 

 vice had been performed, even although no tlieory, nor any spec- 

 ulation had been devised. 



The value of geological research is, therefore, very great, and that 

 of geological theory is certainly much less, although it is highly in- 

 teresting ; theory is constantly fluctuating vi'ith the progress of 

 discovery, and until we have discovered all the facts, we cannot be 

 sure that our theories will stand. With respect to theory and no- 

 menclature, there is therefore, room both for fancy and error j but 

 those who, like Mr. Eaton, have labored hard and long, in investigating 

 facts, and like him, have faithfully reported them, according to the 

 best views which they possessed at the time, are entided to our res- 

 pect and kindness, although their first sketches may possibly require 

 some correction from subsequent observations of themselves and 

 others. The munificence of Gen. Van Rensselaer in promoting geo- 

 logical knowledge, is, so far as we are informed, without a parallel in 

 any country, and he has been fortunate in the field of geological re- 

 search, in which he has employed Mr. Eaton, since it is not only 

 fruitful in scientific facts, of great interest, but in substances of prime 

 importance to society ; and perhaps \ve may yet hope that coal will 

 be added to the other mineral riches of this important region, al- 

 though it may lie at a depth, too great to admit of its being profita- 

 bly explored.* 



Yale College, June 27, 1831. 



* See Mr. Eaton's excellent view of this subject, Vol. XIX. No. I. of this Jour- 

 nal. 



