338 INTEGUMENTS. 



by the exhalents and absorbents, the several orifices of which' 

 he says become distinct by holding it between the eye and a 

 strong light. As it, when raised by a blister, does not allow 

 the effused fluid to pass through any of these pores, it is very 

 reasonably supposed that they are all oblique, and therefore 

 exercise a valvular office on such an occasion. Or if, accord- 

 ing to the supposition of Mr. Cruikshank, the finest pores of the 

 cutis vera are lined by processes from the cuticle, the collapse 

 of these processes on the separation of the cuticle will also ac- 

 count for the fact. It seems to be well ascertained at the pre- 

 sent time, that as the epidermis is more transparent at certain 

 points than elsewhere, the appearance has been mistaken for 

 porosities of exhalents and sbsorbents. The cuticle, when de- 

 tached, will not allow a column of mercury to pass through it y 

 except its weight be so great as to lacerate it : this fact is ra- 

 ther against the doctrine of the pores being visible when exa- 

 mined by permitting the light to shine through, and shows that 

 even those for the hairs and the sebaceous follicles are stopped 

 by some arrangement or other. Upon the whole, the opinion 

 of organized pores in the cuticle for exhalation or absorption, 

 is not sustained by unobjectionable testimony, and is scarcely 

 admissible upon any principle. At the same time it maybe re- 

 marked, that the interstices which exist in it would seem to be 

 sufficient to account for many of the phenomena of exhalation 

 and of absorption. 



The cuticle has but little power of extension, and, conse- 

 quently of contraction, and tears with the application of a very 

 slight force. It naturally contains so little moisture, that its 

 bulk is only inconsiderably altered by drying. Ir, like the hair 

 or nails, resists putrefaction so much, that it has been found in 

 burial places after a lapse of fifty years. When held in water, 

 it swells, becomes white, wrinkles more, loses its transparen- 

 cy, and dulls the sensibility of the cutaneous papilla?. It can- 

 not, like the true skin, be readily reduced by boiling water into 

 gelatine, and consequently, is not affected by tanning: it, in- 

 deed, retards that process, when left on the proximate surface 

 of the cutis vera. When applied to a fire, it burns, like the 

 hair and nails, wilh extreme facility, owing to the presence of 

 a similar oil in it, and it gives out a very disagreeable odour. 



The little extensibility of the cuticle causes it to be ruptured 



