150 THE OCEAN. 
erect. But if such were the construction in the 
Whale, the force with which the water rushes into 
the mouth would inevitably carry a large portion of 
the fluid down upon the lungs, and the animal would 
be suffocated. The windpipe is therefore carried 
upward in a conical form, with the aperture upon 
the top, and this projecting cone is received into the 
lower end of the blowing-tube, which tightly grasps 
it; and thus the communication between the lungs 
and the air is effected by a continuous tube, which 
crosses the orifice of the gullet, leaving a space on 
each side for the passage of the food. 
It is doubtless to give increased power of resist- 
ance to the eye of the Whale in the pressure of 
enormous depths, that there is a peculiar thickness 
in the sclerotic coat. This is the part which in man 
is usually called the white of the eye. “When we 
make a section of the whole eye, cutting through the 
cornea, the sclerotic coat, which is as dense as tanned 
leather, increases in thickness towards the back part, 
and is full five times the thickness behind that it is 
at the anterior part. The fore part of the eye sus- 
tains the pressure from without, and requires no ad- 
ditional support; but were the back part to yield, 
the globe would then be distended in that direction, 
and the whole interior of the eye consequently suffer 
derangement. We see, then, the necessity of the 
coats being thus remarkably thickened behind.”* 
Another no less interesting deviation from ordinary 
structure is found in the skin; the object still being 
defence against external pressure. - Every one is pro- 
* Paley’s Nat. Theol., Bell and Brougham’s edit. p. 40. 
