INTEGUMENTS. 



flHentI/ that the cicatrices of blacks are aTway^ white, We 

 libelieve that this point is not clearly proved. 



Whatever opinion we may form concerning the different 

 ftrata defcribed above, as intervening; between the cuticle 

 and cutis, whether we regard them as iliftind menibraues, or 

 ;as portions detached by art from the cutis, they are of ini- 

 -portance, as containing an extenfive diilribution of capillary 

 veflels. Independently of the colouring matter, thefe vel^- 

 fels feem ordinarily to be filled with wliite fluids : the ex- 

 . haling pores, which fnrnifli the matter of perfpiration, arite 

 from them, and the fame vafcular nct-w tIc is the feat of ery- 

 ■fipelas, and of all the cutaneous eruptions which do not af- 

 feft the corion. 



" The blood," fays Bichat, " does not penetrate this ca- 

 .pillary fyftem in the ordinary Hate; but numerous caufes will 

 lead to its being fuddenly diftcnded. Rub the fl<in a little 

 roughly, and it is inltantly reddened. Irritate it mechani- 

 cally or chemically, its fenfibility is immediately awakened, 

 it becomes filled witi' blood, which could not enter before, 

 and isreddenud in a furface proportioned to the extent of the 

 irritation. The cheeks exhibit an analogous plienoinenon in 

 ^!•l(hing ; and all rubefacient membi-ancs fliew the great 

 • ndency of the fuperficial capillary fvllem to admit, under 



cumftances of excitation, that blood which it rejefts in its 

 ,'. ,tural Hate. Bliliers, and fire, applied to a degree (hort of 

 duftroying the furface, aft in the fame way: they caufe a 

 fudden fpecies of eryfipelas, which is followed by an abund- 

 ant fi-rous exhalation under the ciiticle. 



" Irritation of the flvin is not the only caufe which deter- 

 mines an influx of blood into the exterior capillary fyftem. 

 Whenever the action of the heart is accelerated, and the 

 motion of the blood confequently precipitated, there is a 

 tendency to this paffagc, as we fee clearly after violent exer- 

 cife, or on the accefs of the hot (lage in fevers. 



" The capillary fyllem of the face is more fubjecl to this 

 fudden influx of blood than that of any other part. This is 

 feen in the two cafes juft mentioned, of exercife and fever, 

 •where the aftion of the heart is accelerated. In various 

 difeafes of internal organs the facial capillaries are fympa- 

 thctically affected, and produce rednefs or palenefs of the 

 countenance ; and tlieir dillention always gives to the face 

 in afphyxia a livid tint, which is confined to that part. In 

 deaths refembling afphyxia, where the circulation becomes 

 emban-atfed in the lungs, and in apoplexy, the head is equally 

 remarkable for its lividity. Three circumftances may be 

 ■'noticed, in explanation of this great fufceplibility of the 

 facial capillary fyllem for the admiflion of blood; ill, the 

 ordinary rednefs of the cheeks Ihews that blood is habitually 

 contained in thefe capillaries in a certain quantity, which is 

 not the cafe in other parts ; 2dly, anatomical injetlions fhew 

 us that the arteries communicate here more freely with the 

 capillaries; fine injedtions colour the face much more deeply 

 than other parts ; and, jdly, there is a more acute fenfibility in 

 -the face ; a flight blow will bring the blood into the cheeks 

 in an inflant, although it would produce no rednefs in the 

 arm. 



" The blood quits the capillaries of the face as quickly as 

 it enters them ; the pafhons produce here, almollin iuHan- 

 taneous fucceflion, the lively red of a febrile attack, the 

 deadly palenefs of fyncope, or any intermediate fhades. 

 Thus the face becomes well adapted to fer\-e as a kind of 

 fcenc, painted fuccefhvely by the paflions with numerous 

 fhades, wliich are effaced, return, and undergo a thoufand 

 modifications according to the flate of the mind. 



Let me obferve further on this fnbjeft, that the paffions 

 have a threefold mode of exprcflion in the countenance ; ill, 

 by the capillaries which, being altogether involuntary, often 



betrays what we fhould be iiKlined to conceal ; 2dly, the 

 mufcular motions, which contract or expand the features to 

 e:ipn-r5 the fad or the joyful -affeftions, and thus produce the 



■ wrinkles already noticed ; and, .^dly, the eye, which, as Buffon 

 obfcrves, not only receives fenfitive imprelTions, but alf> 

 exprciFcs mental emotion. The two latter are in fome de- 

 gree voluntary ; we can feign them, although we cannot 

 deceive with tlic firfl. 



"The tendency of the facial capillaries to become diftended 

 with blood, difpofes them to numerous morbid affeftions 

 Eryfipelas frequently attacks' this part ; variolous pulhiles 

 are particularly aftive here; and feveral eruptions -occur 



'more frequently in the face than in other fituations. . 



" We niuft therefore diflinguifli two parts in the capillary 



-fyilem exterior to the corion. One contains habitually- the 

 colouring matter of the /Icin, which is at reft, or' experiences 

 at leaft no other motion, than the fiow and almoft infenfible 

 one of compofition and decompofition, and vhich therefore 

 never exhibits fuch fudden changes as we have jutl defcribed. 

 Though the other fluids are habitually circulated, and are 

 conllantly efcaping by tranlpiration ; their place is often 



•fupplied by blood. We know of no communication be- 



• tween thefe ; they appear to be ablolutely independent. 



■Some white fluid; remain in the latter part at the time of 

 death, as the following experiment will prove. Immerfe a 



■piece of fkin in boiling water for a fhorftime, and the epi- 

 dermis will be elevated into numerous fmall veficles containing 

 a ferous fluid.'' 



The pa^illii of the flcin are fmall eminences of its external 

 furface, fuppofed to perforate the reticular body, and' con.- 

 fequently to be contiguous by iheir extremities to the epi- 

 dermis ; they differ in form in various fituations, and are 

 called villi where they are fmall and fine. Malpighi firft 

 obferved in animals, and particuhu'ly in the foot of the pig, 

 that the external furface of the fkin is not level, but elevated 

 into certain prominences under the cuticle. This ftruftur? 

 does not belong to the whole furface of the cutaneous organ, 

 which, although rather unequal in confequence of fmall 

 rifings about the hairs, has no regularly arranged parts de- 

 ferving to be called papillae. Thus Ruyfdi could find 

 nothing of this kind on the back of the foot, and acknow- 

 ledges that they are obfcure in other parts, and only to be 

 feen after injections ; and other anatomifts have experienced 

 confiderable d'fficulty in detecting thefe parts, even with the 

 affiftance of glaffes. 



" Neither, " fays Bichat," are we to miftake for papilla; 

 the numerous and very fenfible tubercles, which make tlie 

 fl<in of certain fubjects very rough. Thefe confift of fmall eel- 

 lular and vafcular fafciculr, or of febaceous glands found at 

 the openings of the corion under the epidermis, through 

 which the hairs are tranfniitted ; elevate the external furface, 

 and thus caufe projections. Maceration for two or three 

 months converts thel'e bodies, which always contain a little 

 fat, into the firm, whitilh, unftuous and fpermacoti-like 

 fubftance always produced from adipous matter by macera- 

 tion ; the flcin at the fame time becomes foft and pulpy, and 

 is loofencd round thefe tubercles, which are clearly feen to be 

 continuous with the fubjaceiit fat. Thefe prominences are 

 more frequent on the limbs and back than on the "front of 

 the trunk ; and they are more num.erous in the fortner, on 



-the afpect of exteiilion than of flexion. The abl'cnce of 

 thefe rifings, and a confequent fmoothnefs of the outer fur- 



"face of the coiion, belong to our notion of a beautiful fkin ; 

 and this charafter belongs much more to the cutaneous organ 

 of women than of men. The epidermis covering thefe pro- 

 minences is often detached in fcales, particularly by any 

 rather Urong rubbing ; and this contributes ftiil more to the 

 1- f i ro-ugh- 



