While yet a boy, he evinced a fondness for natural history: he collected nearly all the birds of New England and noted their habits.

[1] From 1876 to 1878 he made ornithological surveys to the Lesser Antilles where he discovered 22 bird taxa new to science.

Two of them – the Lesser Antillean flycatcher and the Montserrat oriole – were named in his honor by his colleague George Newbold Lawrence.

In 1881, moved by a desire to see the vestiges of early American civilization, he journeyed through Mexico, and during that and two subsequent trips gathered the material for several books.

On his return from various explorations he prepared accounts of his travels at the request of scientific societies, and later a series of popular lectures, illustrated with photographic views, projected by the magic lantern.