The Three Secretaries 163 



serving nature began when he was still a boy. His early 

 note-books contain systematic lists of various kinds. He 

 gathered specimens of the wood and leaves of plants, and at 

 the age of fourteen joined his elder brother William, who had 

 similar tastes, in making a collection of the game-birds of 

 Cumberland County. Specimens prepared by these boys 

 sixty years ago are still preserved in the National Museum. 



After leaving college, since he was too young to enter any 

 profession, he was allowed to follow his own tastes for a time, 

 and his inclination for science developed in such a remarkable 

 manner that his mother felt that she was justified in allowing 

 him to devote himself for several years to his favorite pur- 

 suits. There were at that time no schools for young natural- 

 ists, and his education was in a large degree self-directed. 

 He began to read medicine, attended a course of lectures at 

 the College of Physicians and Surgeons in New York in the 

 winter of 1841-42, and made excursions, often on foot, in 

 search of specimens and to visit collections. He made long 

 visits to friends in New York, Philadelphia, and Washington, 

 and thus saw the museums and important private collections 

 and became familiar with what were at that time the principal 

 centers of learning. In those days were formed many of the 

 friendships and scientific partnerships which influenced his 

 after life. 



Among his early companions and correspondents were 

 George N. Lawrence (1841), Charles Pickering and John 

 Torrey (1842), John Cassin and James D. Dana (1843), 

 Thomas M. Brewer, Stephen S. Haldeman, Joseph Leidy, and 

 Frederick E. Melsheimer (1844), John G. Morris (1845), 

 Jared P. Kirtland (1847), and Philo R. Hoy and John S. 

 Newberry (1850). 



Still earlier was his friendship with Audubon, with whom 

 he began a correspondence in 1838, and from whom he re- 



