168 
THE RELATION OF ANIMATED BODIES 
the suitableness of the earth and sea to their several in- 
nabitants; and of these inhabitants, to the places of their 
appointed residence! 
Take the earth as it is; and consider the corresponden¬ 
cy of the powers of its inhabitants with the properties and 
condition of the soil which they tread. Take the inhab¬ 
itants as they are; and consider the substances which the 
earth yields for their use. They can scratch its surface, 
and its surface supplies all which they want. This is the 
length of their faculties! and such is the constitution of 
the globe, and their own, that this is sufficient for all their 
occasions. 
When we pass from the earth to the sea , from land to 
water, we pass through a great change; but an adequate 
change accompanies us of animal forms and functions, of 
animal capacities and wants; so that correspondency remains. 
The earth in its nature is very different from the sea, and 
the sea from the earth; but one accords with its inhabitants 
as exactly as the other. 
VII. The last relation of this kind which I shall men¬ 
tion is that of sleep to night; and it appears to me to be 
a relation which was expressly intended. Two points are 
manifest: first, that the animal frame requires sleep; sec¬ 
ondly, that night brings with it a silence, and a cessation 
of activity, which allows of sleep being taken without in¬ 
terruption, and without loss. Animal existence is made 
up of action and slumber; nature has provided a season for 
each. An animal which stood not in need of rest, would 
always live in daylight. An animal which, though made 
for action, and delighting in action, must have its strength 
repaired by sleep, meets by its constitution the returns of 
day and night. In the human species, for instance, were 
the bustle, the labor, the motion of life, upheld by the 
constant presence of light, sleep could not be enjoyed with¬ 
out being disturbed by noise, and without expense of that 
time which the eagerness of private interest would not con¬ 
tentedly resign. It is happy therefore for this part of the 
creation, I mean that it is conformable to the frame and 
wants of their constitution, that nature, by the very dispo¬ 
sition of her elements, has commanded, as it were, and 
imposed upon them, at moderate intervals, a general inter¬ 
mission of their toils, their occupations, and pursuits. 
But it is not for man, either solely or principally, that 
night is made. Inferior, but less perverted natures, taste 
its solace, and expect its return with greater exactness 
and advantage than he does. I have often observed, and 
