0128 



Scent. 



(Carpenter, Hum. Pliys. 632). The greater proportion of this solid 

 matter appears to be a protein-compound in a state of incipient de- 

 composition. Urea also has been detected in it. Now both urea 

 and protein compounds^ under the influence of decomposing agencies, 

 are active as well as important elements in the production of am- 

 monia, a distinct salt of which substance moreover is found in the 

 azotised matter under mention. Now, processes strictly analogous — 

 not to say identical — with this of transudation in man are known to 

 take place in all the warm-blooded animals,* differing only, it is 

 probable, in the degree to which, in the different classes of animals, 

 the process is severally carried on. 



Hence then we are at liberty to infer that an ammoniacal element 

 is one of the accessories, if not constituents, of scent in the extended 

 acceptation of the word. 



It may be as well, perhaps, while noticing these peculiarities or 

 phenomena of transudation, to notice also in this place, rather than 

 further on, the fact that cutaneous excretion is complementary to, or 

 vicarious with, renal excretion. Thus, Dr. Carpenter says, — "The 

 cutaneous excretion, as already pointed out, is in great degree 

 vicarious v^ith the urinary, in regard to the amount of fluid 

 eliminated ; the urine being more watery in proportion as the 

 cutaneous exhalation is diminished in amount, and vice versa. But 

 we are also to look at these two excretions as vicarious in regard to 

 the elimination of the products of the ^ waste' of the system. The 

 share which the skin has in this office has probably been generally 

 under-rated. There is reason to believe that at least 100 grains 

 of azotised matter are excreted from it daily ; and any cause which 

 checks this excretion must throw additional labour on the kidneys, 

 and will be likely to produce disorder of their function." (Hum. Phys. 

 631). Now in man — and there is no doubt that a perfect analogy 

 exists in these matters between man and the lower animals — " the 

 quantity of urea secreted at any given period of life seems to depend 

 mainly on two conditions — namely, the degree of muscular exertion 



* " The sliin, in most of the Mammalia, is an important excreting organ, being 

 usually furnished with a multitude of glandulae, which discharge their products upon 

 its surface. The products of these glaudukne vary considerably in difierent animals, 

 and in different parts of the same animal. The ordinary perspiratory glands draw off 

 watery fluid from the blood, with a small quantity of excretory matter closely 

 resembling that which is eliminated by the kidneys." (Princ. Phys. 547. See 

 also Id. 777), 



