146 LIFE OF BENJAMIN SILLIMAN. 



prejudices. We can have no occasion to fear such an at 

 tack, and must judge when the work appears whether it is 

 worthy of a reply. 



TO DR. EDWARD HITCHCOCK 



NEW HAVEN, May 25, 1841. 



MY DEAR SIR, Before yours of the 20th arrived, I had 

 already laid out, to go by Mr. Shepard, Agassiz's plates of 

 the glaciers, and also the plates of several other of the 



works of the same author I confess myself unable 



as yet to give an opinion worthy of your attention on the 

 theory of Agassiz. Dr. Mantell writes me that it has a 

 great run among the geologists, but he thinks they have 

 too eagerly jumped to a conclusion, and evidently holds 

 back. I shall study it as soon as possible, but my time 

 my time ! I have just taken up my pen again after an in 

 terruption of five or six hours by a succession of strangers. 

 I return your proof, altering only one word. I am glad that 

 Mr. Lyell stands acquitted of infidelity. You may remem 

 ber I did not judge him quite so unfavorably as you did. 



TO DR. EDWARD HITCHCOCK. 



NEW HAVEN, October 13, 1855. 



I ADMIRE your courage in securing that grand 



specimen from Turner's Falls, and I hope one day to see it, 

 and, perhaps, other acquisitions. Should our early conclu 

 sions be subverted, and should we be drawn from an aviary 

 into a frog-pond, we must even submit and agree to croak, 

 if we may not cackle or crow. Fiat verttas ! We were 

 much amused by Professor Shepard's brilliant thought, 

 whereby, also, hangs a tail, of a reptile if not of a struthi- 



ous bird or other bird that wore a tail Need we 



give up the birds ? To my eye, many very many of 

 the impressions appear as indubitably ornithic as tracks of 

 indubitable living birds, made yesterday in clay or mud, and 

 so said the acute and unprejudiced President Day, when he 



