CHRONOLOGY xxxix 



1843 



March 11. At fifty-eight, sets out with four companions for 

 the region of the Upper Missouri and Yellowstone Rivers, 

 but is unable to attain his long desired goal, the Rocky 

 Mountains. 



November. Returns with many new birds and mammals. 



1845-1846 



The Viviparous Quadrupeds of North America, in collabora- 

 tion with the Rev. John Bachman, issued to subscribers 

 in 30 parts of five plates each, without letterpress, making 

 two volumes, imperial folio, at $300.00. 



John W. Audubon, traveling in Texas, to collect materials for 

 his father's work. 



1845 



Engrossed with drawings of the Quadrupeds, in which he re- 

 ceives efficient aid from his sons. 



July 19. Copper plates of The Birds of America injured by 

 fire in New York. 



December %4- Bachman, his collaborator, issues ultimatum 

 through Harris, but work on the Quadrupeds, which had 

 come to a stand, is resumed. 



1846-1847 



John W. Audubon in England, painting subjects for the illus- 

 tration of the Quadrupeds of North America. 



1846-1854 



The Viviparous Quadrupeds of North America, in collabora- 

 tion with John Bachman, published in three volumes, 

 octavo, text only, by J. J. and V. G. Audubon; volume i 

 (1847) only appeared during the naturalist's lifetime. 



