498 LOUIS AGASSIZ. 



grossing to allow him to follow this line of 

 investigation closely, but it was never absent 

 from his view of the animal kingdom as a 

 whole. He valued extremely Mrs. Holbrook's 

 thoughtful sympathy, and as the following 

 letter connects itself with the winter evening 

 talks by the " Hollow Tree " fireside, and was 

 suggested by them, it may be given here, 

 though in date it is a little in advance of the 

 present chapter. 



TO MRS. HOLBROOK. 



Cambridge, July, 1852. 

 ... I am again working at the human 

 races, and have opened another line of inves- 

 tigation in that direction. The method fol- 

 lowed by former investigators does not seem 

 to me to have been altogether the best, since 

 there is so little agreement between them. 

 The difficulty has, no doubt, arisen on one 

 side from the circumstance that the inquirer 

 sought for evidence of the unity of all races, 

 expecting the result to agree with the pre- 

 vailing interpretation of Genesis ; and on the 

 other from too zoological a point of view in 

 weighing the differences observed. Again, 

 both have almost set aside all evidence not 

 directly derived from the examination of the 



