340 INTEGUMENTS. 



tion, in a great measure, it does not do so entirely ; for, after 

 a subject has been kept some time, its fingers, toes, nose, and 

 ears get very dry and hard. 



During life the process of perspiration is continually going 

 on, either in a sensible or insensible manner; and according to 

 the experiments of Sanctorius, more than one-half of the 

 weight of our food is lost in that way through the skin and 

 lungs. MM. Lavoisier and Seguin ascertained that the propor- 

 tionate exhalation from these organs was eleven of the former 

 to two of the latter. When the perspiration is rapid, it assem- 

 bles on the surface of the body in the form of small drops, 

 having an acid, saltish taste, and a peculiar odour. In this 

 state, according to the analysis of Berzelius, it consists princi- 

 pally in water, holding in solution a hydrochlorate of soda and 

 of potash, some lactic acid, lactate of soda, and a little animal 

 matter. The perspiration, besides its use as an excretion, is 

 a powerful means, by its evaporation, of enabling the body 

 to resist a high temperature. It varies, both in quality and 

 quantity, according to age, sex, state of health, food, and habits 

 offife. 



The power of the cuticle to absorb or to transmit inwardly 

 articles through it, is not by any means so obvious as its exha- 

 lation: the facts, however, upon the whole, seem to prove that 

 though this power is much curtailed when compared with that 

 possessed by mucous surfaces, yet it does exist to a certain ex- 

 tent.* 



CHAPTER II. 



OF THE SEBACEOUS ORGANS OF THE SKIN. 



THE Sebaceous Organs consist in Follicles (Cryptce, Mucosa) 

 and Glands, (Glandules Sebacece.) They furnish the oily exha- 

 lation, which lubricates the surface of the skin, gives linen, 

 when worn a long time, a greasy appearance, and causes the 



A 



* Wistar's Anat. Vol. ii. p. 396, 3d edit. 



