Sep. I. 2. 1, THEORY OF FEVER. 449 



these absorbents and veins generally occurs along with that of 

 the capillaries, as appears by the dry skin in hot fits of fever; 

 and from there being generally at the same time no accumula- 

 tion of venous blood in the cutaneous vessels, which would ap- 

 pear by its purple colour. 



II. Cwnpound Fever. 



I. When other parts of the system sympathize with this tor- 

 por and orgasm of the cutaneous capillaries, and of the heart 

 and arteries; the fever-fit becomes more complicated and dan- 

 gerous; and this in proportion to the number and consequence 

 of such affected parts. Thus if the lungs become affected, as 

 in going into very cold water, a shortness of breath occurs; 

 which is owing to the collapse or inactivity (not to the active 

 contraction or spasm) of the pulmonary capillaries; which, as 

 the lungs are not sensible to cold, are not subject to painful 

 sensation, and consequent shuddering, like the skin. In this case 

 after a time the pulmonary capillaries, like the cutaneous ones, 

 act with increased energy; the breathing, which was before 

 quick, and the air thrown out at each respiration in less quan- 

 tity, and cool (.0 the back of the hand opposed to it, now becomes 

 larger in quantity, and warmer than natural; which however 

 is not accompanied with the sensation of heat in the membrane, 

 which lines the air-vessels of the lungs, as in the skin. 



2. One consequence of this increased heat of the breath is 

 the increased evaporation of the- mucus on the tongue and nos- 

 trils. A viscid material is secreted by these membranes to pre- 

 serve them moist and supple, for the purposes of the senses of 

 taste and of smell, which are extended beneath their surfaces; 

 this viscid mucus, when the aqueous part of it is evaporated by 

 the increased heat of the respired air, or is absorbed by the too 

 great action of the mucous absorbents, adheres closely on those 

 membranes, and is not without difficulty to be separated from 

 them. This dryness of the tongue and nostrils is a circumstance 

 therefore worthy to be attended to; as it shews the increased 

 action of the pulmonary capillaries, and the consequent increas- 

 ed heat of the expired air; and may thus indicate, when colder 

 air should be admitted to the patient. See Class I. 1.3. 1. 

 The middle part of the tongue becomes dry sooner, and recovers 

 its moisture later, than the edges of it; because the currents 

 of respired air pass most over the middle part of it. This how- 

 ever is not the case, when the dryness of the tongue is owing 

 only to the increased mucous absorption. When, however, a 

 frequent cough attends pulmonary inflammation, the edges of 



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