INFLAMMATIONS. 7 



of inequality in the distribution of the blood may throw an un- 

 usual quantity of it upon particular vessels, to which it must 

 necessarily prove a stimulus. But, further, it is probable, that 

 to relieve the congestion, the vis medicatrix naturae increases 

 still more the action of these vessels ; and which, as in all other 

 febrile diseases, it effects by the formation of a spasm on their 

 extremities. 



CCXLV. A spasm of the extreme arteries, supporting an 

 increased action in the course of them, may therefore be con- 

 sidered as the proximate cause of inflammation ; at least in all 

 cases not arising from direct stimuli applied ; and even in this 

 case the stimuli may be supposed to produce a spasm of the ex- 

 treme vessels. 



CCXLV I. That, in inflammation, there is the concurrence 

 of a constriction of the extreme vessels, with an increased action 

 in the other parts of them, seems probable, from the considera- 

 tion of rheumatism. This is a species of inflammation which 

 is often manifestly produced, either by cold applied to over-dis- 

 tended vessels, or by causes of an increased impetus, and over- 

 distention in vessels previously constricted. Hence the disease 

 especially appears at seasons liable to frequent and considerable 

 vicissitudes of heat and cold. 



To this we may add, that the parts of the body most fre- 

 quently affected with inflammation, are those exposed both to 

 over-distention, from a change in the distribution of the fluids, 

 and, at the same time, to the immediate action of cold. Hence 

 quinsies and pneumonic inflammations are more frequent than 

 any others. 



CCXLVII. That the spasm of the extreme vessels takes 

 place in inflammation, is to be further presumed from what is at 

 the same time the state of the whole arterial system. In every 

 considerable inflammation, though arising in one part only, an 

 affection is communicated to the whole system, in consequence 

 of which an inflammation is readily produced in other parts 

 besides that first affected. This general affection is well known 

 among physicians, under the name of the Diathesis Phlogis- 

 tica. It appears most commonly in persons of the most rigid 

 fibres is often manifestly induced by the tonic or astringent 

 powers of cold is increased by all tonic and stimulant powers ap- 



