64 OF VITAL MOTION. 



itself supposititious, is not sufficient to account for the 

 results. 



In maniacal frenzy, on the other hand, where there 

 is a superabundant generation of nervous force, the 

 results would seem to be entirely opposed to those 

 which have just been considered. The hot and red- 

 dened skin, and the full pulse, necessitate, indeed, a 

 distended state in the fibrous elements of the vascular 

 coats; and the obstinate constipation of the bowels, 

 and the retention of urine, which are such frequent 

 symptoms of this condition, are facts which argue the 

 existence of a state opposed to contraction in the walls 

 of the viscera concerned. 



(b.) Of the organic forces, not of a nervous cha- 

 racter, as agents in the movements under 

 consideration. 



The influence of the blood upon the coats of the 

 small vessels, and consequently upon the muscular 

 fibres contained in these coats, has been considered in 

 the last chapter ; and it has been seen that this in- 

 fluence, whatever it may be, does not give rise to 

 contraction. Wherever the blood possessed peculiarly 

 stimulating properties, whether in consequence of a 

 formation from rich pabulum, or as the result of 

 perfect oxygenation, on these occasions the vessels 

 are freely distended ; and, on the contrary, whenever 

 the blood is pale and watery, and the respiration 



