AND ANIMAL LIFE. 101 



is more perfectly formed at this period than the 

 latter, because more early brought into requisi- 

 tion, yet it is manifest, that, for some time after 

 birth, its action is too feeble to constitute an 

 expensive function of the system. 



XC. It may probably be advanced against 

 the present argument, that the rapid progress of 

 the infant, evinced in the expansion of the body, 

 demonstrates that the functions appropriated 

 to organic life are more active than those of the 

 adult. This idea seems plausible at the first 

 glance ; but if it be remembered that the child 

 is subject to little or no exertion ; that its waking 

 and sleeping moments are unruffled by real or 

 imaginary evils ; that its digestive powers are 

 not deranged by the improprieties of habit, or 

 the influence of moral causes ; and, lastly, that 

 its existence may be said to be distributed into 

 three parts, two of which are devoted to sleep, 

 or a state equivalent to it, and the other to the 

 breast, it will then appear obvious, that this 

 effect does not require superior internal energy 

 on the part of the assimilating organs to give an 

 efficient reason for its occurrence. 



XCL The embonpoint of the system in adults 

 depends less on the quantity or quality of 

 food than is generally imagined. Rest, peace of 

 mind, and a moderate indulgence of our passions, 

 are the principal agents which contribute to pro- 

 duce this result. Indeed the more nearly we 



