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Chapter III. 



DECLINE OF THE SYSTEM. 



To follow minutely the various steps by which 

 Nature conducts the individual to its state of 

 maturity, would engage us in details incom- 

 patible with the limits of the present work. 

 I shall only remark, in general, that during the 

 period when the body is intended to increase in 

 size, the powers of assimilation are exerted to 

 prepare a greater abundance of nourishment, so 

 that the average supply of materials rather ex- 

 ceeds the consumption : but when the fabric has 

 attained its prescribed dimensions, the total 

 quantities furnished and expended being nearly 

 balanced, the vital powers are no longer exerted 

 in extending the fabric, but are employed in 

 consolidating and perfecting it, and in qualifying 

 the organs for the continued exercise of their 

 respective functions, during a long succession of 

 years. 



Yet, while every function is thus maintained 

 in a state of healthy equilibrium, certain changes 

 are in progress which, at the appointed season, 



