294 DERMOID SYSTEM. 



Q. There are two phenomena in gangrene carefully to 

 be distinguished, what are they? 



#. The mortification of the part, and the putrefaction 

 of the mortified part. 



Q. What hastens the putrefaction of the mortified part? 



*#. The process is rapid in proportion to the quantity 

 of blood it contains. 



Q. Then antisceptic is a relative term, to be under- 

 stood in a double sense? 



t/2. It is; for it may prevent the mortification of a 

 part, and also the putrefaction of a part already mortified. 

 How different are these two objects. 



Q. In what distinctive sense are the exhalation and 

 solution of transpired fluids to be understood? 



/?. In this, that the exhalation of the perspiration is a 

 vital phenomenon ; its solution in the air is physical. They 

 are totally independent of each other. 



Q. Sweating, then, is owing to two causes wholly in- 

 dependent of each other, what are they ? 



*fl. The one is the increase of exhalation, the other is a 

 diminished solution by the air of what is exhaled. 



Q. What are the several causes which increase exhala- 

 tion by the skin? 



/?. Whatever increases the determination of fluids to 

 the surface, as severe exercise, fever, &c. are one set of 

 causes. The exhaled fluid is increased by external causes, 

 which relax and expand the cutaneous organ, as the heat 

 of summer, warm bathing, &c. The action of the skin is 

 sympathetically increased in diseases; you see this in the 

 sweats of phthisis. The passions, by acting on the epi- 

 gastric organs, increase sweating by sympathy. 



Q. What effect has bathing in water on the skin? 



