OF THE SKIN IN GENERAL. 219 



ticularly on its superficial face; by the epidermis, of which we 

 have been speaking, and by the intermediate mucous body, 

 offering, thus, a diminution of organization, and of vitality, 

 from the dermis to the epidermis, partakes of the physical, 

 chemical, and vital properties of these various parts. It is the 

 same with respect to its functions or organic actions. 



312. The skin, on account of the dry and slightly permea- 

 ble epidermis, which makes a part of it, is not so well adapted 

 for absorption and secretion as the mucous membrane. 



The skin being furnished with its epidermis, in a state of 

 integrity, cutaneous, or as it is also called, cuticular, absorp- 

 tion, is in fact, to this day, a subject of doubt and discussion 

 among physiologists. To decide this question between Seguin, 

 Currie, Klapp, Rousseau, Dangerfield, Chapman, Gordon, Ma- 

 gendie, &c. , whose observations and experiments go to dis- 

 prove the existence of cutaneous absorption, and Keil, Haller, 

 Percival, Home, Ouikshank, Watson, Forci, Abernethy, Bi- 

 chat, Duncan, Kelly, Bradner, Stewart, Sewall, &c., and M. 

 Young in particular, whose experiments and observations are 

 in favour of this absorption, we must abstract all those cases, 

 and they are numerous, in which absorption may have taken 

 place by respiration, as well as by the skin: those in which the 

 epidermis may have been softened, altered, or abraded by con- 

 tinued applications to its surface, or by repeated rubbings, un- 

 der which circumstances, absorption is no longer cuticular, but 

 of the same kind to that which takes place in the mucous mem- 

 brane, or by inoculation, when the matter is carried through 

 the divided epidermis into the corpus mucosum,and even into 

 the dermis, both parts being eminently absorbent. When this is 

 done, there remains a small number of facts, which show, that 

 certain substances are absorbed by the skin, through the epi- 

 dermis, in its entire state, but that this membrane is truly an 

 obstacle that very often prevents the absorbent power of the 

 external tegument. 



313. The skin is also an organ of secretion and excretion. 

 Two kinds of well known extrinsic secretion take place in 

 this membrane, cutaneous perspiration and the sebaceous fol- 

 licular secretion. Perspiration is sometimes vaporous and 



