CHAPTER IV. 



A DECADE OF WORK AT HOME. 



1840-1850. 



ON Dr. Gray's return from Europe, the University 

 of Michigan not yet needing his services, he settled 

 in New York to work on the "Flora of North 

 America." 1 



In 1841 he made his first journey to the mountains 

 of North Carolina, of which he wrote an account in the 

 "American Journal of Science " in the form of a 

 letter to Sir William Hooker. 



The country west of the Mississippi was just now 

 opened to exploration, and for some years continued 

 to afford an immense amount of new material to the 

 botanist. Dr. Gray, and his friends Dr. Torrey and 

 Dr. Engelmann especially, interested themselves in 

 sending collectors with the various expeditions, ex- 

 plorations, boundary surveys, etc., and were kept very 

 hard at work in studying and distributing the several 

 collections as they came in. The difficulties of com- 

 munication were great, postage was very dear, and 

 the post-office rule that sheets, no matter of what 

 size, could be sent as one letter, while the addition of 



1 A Flora of North America ; containing abridged descriptions of 

 all the known indigenous and naturalized plants growing north of 

 Mexico ; arranged according to the natural system. By John Torrey 

 and Asa Gray. New York. 8vo ; vol. i., 1838-1840, pp. xvi, 711 ; 

 vol. ii., 1841-1843, pp. 504. 



