18? 



degrees of Reaumur's thermometer, its albuminous parts would suddenly 

 coagulate, obstruct all the vessels, interrupt the circulation, and destroy 

 life. When, therefore, from an increased activity of the nutritive com- 

 binations, a greater quantity of heat is disengaged, the animal economy 

 parts with it, and if is taken up, in greater quantity, by the surrounding 

 bodies. This accounts for the equality of the temperature of the inter- 

 nal parts of the body, in old people, and in children, notwithstanding the 

 difference of their temperature externally. The difference consists in 

 this, that where most caloric is produced, most is given out; and though 

 the blood and urine in old people, as well as in the young, are at thirty- 

 two degrees, what a difference is there not, between the hot and pene- 

 trating perspiration which is poured in abundance from the child, and 

 the dryness and coldness of the skin in old people; between the sweet 

 and warm breath of the former, and the frozen breath of the latter! 

 Hence the opinion so generally received and of such antiquity, that old 

 people are benefited by cohabiting with the young. Thus we are told, 

 that David had a young virgin brought to him, that he might lie with 

 her, and get heat in his limbs that were stiffened with years. 



If it be true, that in the very act of nutrition, which converts our fluids 

 into solids, there is disengaged a considerable quantity of caloric; the 

 motion of nutritive decomposition, by which our solids are converted into 

 liquids, must cause an equal quantity of heat to be absorbed. The ob- 

 jection is a very strong one, and not easily got over; it may be answered, 

 by observing, that all living bodies, from the instant of their formation, 

 contain a certain quantity of caloric which they retain, so that this double 

 process of acquiring heat and parting with it, the unavoidable result of 

 nutritive composition and decomposition, merely keeps up an equili- 

 brium, and maintains the same degree of temperature. 



The blood which becomes saturated with oxygen, in the capillaries of 

 the lungs, parts with that principle, and disengages its caloric, through- 

 out the capillary vessels of the whole body, of which each organ must 

 set free a greater quantity, in proportion to the activity of the living prin- 

 ciple, and to the rapidity of the circulation. The parts through which 

 the greatest number of vessels circulate, perhaps give out most caloric, 

 and communicate a portion of it the organs, which receive but a small 

 quantity of blood, as the bones, the cartilages, Sec. It is easy to under- 

 stand, why an inflamed part, through which the blood circulates with 

 more rapidity, and whose sensibility and contractility are much increased, 

 is manifestly hotter to the feel of the patient and of the physician, though, 

 as was observed by John Hunter, a thermometer applied to the inflamed 

 part, shows a scarcely perceptible increase of temperature. He injected 

 into the rectum of a dog, and into the vagina of an ass, a strong solution 

 of oxymuriate of mercury. Acute inflammation came on, the swollen 

 mucous membrane formed, externally, a considerable projection. Blood 

 flowed from the torn capillaries, yet the thermometer rose very slightly, 

 only one degree of Fahrenheit's. But, however slight that increase of 

 heat in the inflamed part, it is very sensibly felt, on account of the ex- 

 treme sensibility of the organ, whose vital properties are all increased*. 

 The liveliness of impressions being proportioned to the degree of the 

 power of sensation, one need not wonder that the patient should experi- 



* Whose capability to resist or proper tone is very much diminished Godmau, 



