ON ORGANIC AND ANIMAL LIFE. 
134 
sion. Every dam has a call for her young, and in every flock or 
herd there are signs that bring numbers together; signs of en¬ 
joyment or suffering, of desire or aversion; and even among 
rivals and enemies there are signs of alarm, of defiance, or 
rage*.” In the congregation of mere animals, it is true that 
the motives to union on the one hand, or the occasions to strife 
on the other, are comparatively few, instinctive, and simple : 
the troops they compose are uniform in their manner; herds 
merely pasturing together, in the manner of a family, united 
under a common parent or head, and co-operating in the per¬ 
formance of the same work together. Whilst in human nature 
the associating principle is combined with a variety of considera¬ 
tions and circumstances which lead mankind to vary their forms 
indefinitely. 
But with respect to organic life, there is no difference between 
man and the brute creation. The organs which are to perform 
the function of life in both are no sooner created and perfected, 
than they commence their labour, and are as perfect in the 
young animal as in the adult. This is the life by which all the 
parts of the body are kept in repair:— 
“ The watchful appetite was given 
Daily w ith fresh materials to repair 
The unavoidable expense of life, 
The necessary waste of flesh and blood." 
Food proper for nutrition is first submitted to the operation of 
digestion, is then thrown into the circulation, undergoes in the 
lungs the changes which respiration is intended to produce, and 
is at length distributed to the organs, to be applied to their nutri¬ 
tion ; from thence, after a certain period, it is taken away by ab¬ 
sorption, thrown again into the circulation, and finally discharged 
from the system by means of the several exhalations and secretions. 
According, then, to the theory which we have adopted 
(Bichat’s), living systems are endued with certain properties, 
powers, or principles, the chief of which are those of feeling and 
moving, by whose possession their organs are rendered capable 
of performing the functions upon which the continuance of life 
depends. We must consider, then, life as that state of being 
produced by the possession and exercise of certain vital proper¬ 
ties, and not, as is commonly supposed, to consist in any single 
principle. Richerand, Hunter, and others, supposed that a 
vital principle exists, which incessantly watches and guards 
over the whole machine; a kind.of preserving principle that 
* Fergusoifs Mural Science. 
