60 THE ARCHITECTURE OF BIRDS. 
head seemed as numerous and as extensive as ever. 
Long after this I observed them in large bodies, that 
continued to pass for six or eight minutes, and these 
again were followed by other detached bodies, all 
moving in the same southeast direction till after six 
in the evening. ‘The great breadth of front which 
this mighty multitude preserved would seem to inti- 
mate a corresponding breadth of their breeding-place, 
which, by several gentlemen who had lately passed 
through part of it, was stated to me at several miles. 
It was said to be in Green county, and that the 
young began to fly about the middle of March. On 
the 17th of April, forty-nine miles beyond Danville, 
and not far from Green River, I crossed this same 
breeding-place, where the nests for more than three 
miles spotted every tree; the leaves not being yet out, 
I had a fair prospect of them, and was really aston- 
ished at their numbers. A few bodies of pigeons 
lingered yet in different parts of the woods, the roar- 
ing of whose wings were heard in various quarters 
around me. All accounts agree in stating that each 
nest contains only a single young one. These are 
so extremely fat, that the Indians and many of the 
whites are accustomed to melt down the fat for 
domestic purposes, as a substitute for butter and 
lard. At the time they leave the nest they are nearly 
as heavy as the old ones, but become much leaner 
after they are turned out to shift for themselves.”* 
The platforms, however, which are thus built by 
some of the pigeon family, are mere miniatures of 
the strong, substantial, and extensive structures of 
the same kind which are formed by a considerable 
number of birds of prey (Falconida, Leacu). Among 
these platform-builders on the large scale, we have 
the griffard, or martial eagle (Aguila bellicosa) of 
Southern Africa, a powerful bird, which preys on an- 
telopes, hares, and similar animals, and is in the habit 
of soaring so highas to elude the sight. According 
* Wilson’s Amer. Ornith., v., 207 
