BIRDS. 
309 
so that a bird, with its flying feathers on the stretch, 
would fall much more slowly than one would suppose from 
the difference between its specific gravity and that of the 
air. 
“ The resistance which all the feathers on the body of 
the bird offer to motion backwards is still greater ; and it 
increases with the force which tends to move the animal 
in that direction. The instant that it begins to be driven 
backwards, so that a current against its body is produced, 
the points of the feathers rise, and take the wind with so 
many fibres, that the resistance is very similar to that 
made by a scaly fish, when one attempts to draw one of 
these by the tail ; and every one who has angled, and acci- 
dentally caught even a common trout in that way, knows 
that an ounce w T cight is as difficult to laud when so hooked 
as a pound weight is when hooked by the head. But the 
feathers of birds rise much more in proportion than the 
free edges of the scales upon any fish ; and they are every 
way as well formed for holding on in the air, as those are 
for holding on in the water. Thus the bird may he said 
to resist motion backwards in the air, by throwing out the 
point of each feather like the fluke of an anchor.”* 
The jaws of a Bird are not furnished with teeth, as are 
those of a Fish, an Amphibian, a Reptile, or a Mammal, 
for the purpose of seizing, dividing, or chewing the food. 
The place of these organs is effectually supplied by a casing 
of horn, terminating in a point at the tip, and brought to 
an edge on each side of each jaw. This modification is 
familiarly known to us as the beetle or bill of the Bild. In 
the Birds of prey, the beak is a keen carving-knife; the 
♦Mudie’s “Nat. Hiat, ofBirds,’' 37. 
