202 LIFE OF BENJAMIN SILLIMAN. 



rived safely and has cost you no more. I shall be much 

 gratified with the medallion, which I hope you will have 

 executed to your satisfaction. I have heard Mr. Lyell 

 three times, having gone to Boston on purpose, (and B 

 after me,) and also to see his fine illustrations, a few of 

 them very magnificent in dimensions and in execution. 

 He is certainly not a fluent and easy lecturer ; but his dig- 

 nity, simplicity, truth, great personal experience, candor, 

 and logical exactness, have won for him the confidence and 

 esteem of a thinking people, disciplined, even in the 

 middle ranks, to strict intellectual attention. 



FROM DR. MANTELL. 



June 7, 1842. 



A VERY elaborate paper of Mr. LyelPs on your 



tertiary and crustaceous strata was read lately, of which an 

 abstract appears in this week's "Athenaeum." It is not 

 very lucid, and appears to me to abound in those trivial- 

 ities of percentage which are not of sufficient importance 

 to justify any important generalizations. Every day is 

 showing the fallacy of trusting to negative evidence. Agas- 

 siz's geological distribution of fishes must already undergo 

 important modifications ; and the scenes (cenes) if you 

 will allow a pun of LyelPs tertiary drama will have to 

 be shifted as often as in a pantomime. But this is heresy, 

 so breathe it not ! I saw poor Mr. Bake well last week ; 

 he has still mental energy, but is as deaf as a post, and 

 very helpless indeed. Notwithstanding what your son as- 

 sures me, and Mr. Lyell's opinion, I still think Professor 

 Hitchcock's bird-tracks will be found to be reptilian. I 

 have heard but once from Mr. Lyell since he left England. 

 Mr. Murchison's memoirs on the geology of Russia will 

 appear in a separate work in the course of next spring ; 

 his soirees were very brilliant and well attended. At Lord 

 4 Northampton's, (the President of the Royal Society,) 

 Washington Irving was present, but I was not there on 



