138 PHYSIOLOGY OF ORGANIC LIFE. 



sels, at the first periods of life, were equal to 

 those of the chylous, and secretory, the sys- 

 tem would remain stationary in infancy, as it 

 does at the period of manhood, without ever 

 arriving at it ; and, on the contrary, if the ac- 

 tions of these vessels were not greater in old 

 age, than in infancy and manhood, there would 

 scarcely be in the system any diminution in its 

 size ; the whole would be like an evergreen, ne- 

 ver, perhaps, liable to perish or decay. But, 

 alas ! this period of decay does arrive ; it is 

 brought on by the loss of balance, between the 

 vessels subservient to the growth, and to the 

 decrease of the system. In the common course 

 of nature, the change is gradual and impercep- 

 tible, but it, nevertheless, is constant and unin- 

 terrupted. The arteries, with relation to the 

 veins, are small in size ; and the veins, on the 

 contrary, are large with relation to the arte- 

 ries ; all, all is waste, and no supply : the 

 power whick the different organs originally 

 possessed, of imparting any vital energy to the 

 different substances that are applied to them, 

 and even of retaining their own, becomes lost, 

 and a total abolition of all sense and sensa- 

 tion, of all consciousness and voluntary mo- 

 tion, ensues. The different muscles, volun. 

 tary involuntary and mixed, whose actions de- 

 pended on the energy they ought to receive 

 from the matter contained within the cavity 



