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 255 Part VI. ANA T o M Y. Thofe which are found in the hairy fcalp, fcrotum, <bc. fteeping it in water, and by the biifterS raifed bn the flan by veficatories. It yields very much infwellings ; but are fail of other kinds. The papillae of the firft and fecond kinds appear to be not fo much as the flcin, without breaking or crocking. furrounded at their bales by a foft mucilaginous and, Hard and reiterated fridtions loofen it infenfibly, and pretty vifcid fubliance, which fills the ioteiftices between prefently afterward, a new llratum arifes, which thruils; them, and reprefents a kind, of net-work or heve, the- the firft outward, and may itfelf be loofened and thrult maihes or holes of which furround each papilla. Tins outward by a third ftratum, .and fo on fubftance is commonly called corpus reticuLxre, or mu- The epidermis adheres very clofely to the cutaneous papilias, from which it may be feparated by boiling; or eojtm. This vafcular texture is of various forms .and figures by fteeping, for a long time, in cold water. It adheres ftiil cTofer to the-corpus reticulare, which in the different parts of the body. The inner furface of the fkin is covered by very fmall is eafily raifed along with it; and they feem to be true of each other. tubercles, commonly called cutaneous glands, or gian- portions or continuations The.epidermis1 covers the flcin through its whole exdula millares, Thefe tubercles are partly fixed in fmall foffulae, in tent, except at the places where the nails lie. It is the fubftance of the flcin, winch anlvver to .the fame marked vvith the fame furrows and lozenges as the fkin, number of fmall cavities in the corpus aclipofurn. Their and has the fame openings and pores ; and though it may excretory dudls open on the outer furfaqe of the fkin, be faid to pafs the hounds of the flcin, where it is contifometimes in the papillae, and fometimes on one fide of nued inward, through the great op .rungs, yet at thefe tirem. places it lofes the name of epidermis. The gneateft part of them furnifhes fweat, and others When we examine narrowly the fmall pores or holes, a fatty oily matter of different tiiickneftes, as in the hairy through which the fweat pafles, the epidermis feems to fcalp, in the back, behind the ears, and at the lower enter thefe, in order to compleat the excretory tubes of part of the nofe, where this matter may be fqueezed out, the cutaneous glands.- The foflulse of the hairs have in form of fmall worms. likewife the fame produ&ions of the epidermis, and it Befides thefe corpufcles, there are other fniall folid feems to give a foit of coat or bark to the hairs thembodies, almoft of an oval figure, contained in the fuh-; felves. Laftly, the aimoft imperceptible duds of the cu-_ ftanCe of the flein. 'Thefe are the roots or bulbs from taneous poreS are lined by it. whence the hairs arife, and fame of them are fituated withirr the inner furface of the fkin. USES OF THE SKIN. The flcin has feveral confiderable openings, fome of which have particular names ; fuch as the fifl’ure of the It is chiefly and properly the filamentary fubftance, palpebrse, the nares, the mouth, the external foramen called the body of the fkin, which is the univerfaj inteof the ears, the anus, and openings of the parts of ge- gument of the body, and the bafis of all the other cutaneration. neous parts; each of vhkh has its particular: ufes. Befides thefe, it is perforated.by an infinite number of The flcin is able to refift external injuries to a certain fmall holes, called pores, which are of two kinds. Some degree, and fuch iinpreifions, fiidipns, ftrokes, to are more or lefs perceivable to the naked eye.; fuch as which the human body is often liable, as would hurt, the orifices of the milky dudls of the .mammas, the ori- wopnd, and diforder the parts of which it is compofed, fices of the excretory canals of the cutaneous glands, if they were not defended by the fkin. and the paffages of the hairs. papillae, are the organ of feeling, and contribute The other pores are imperceptible to the naked eye, to1 The an univerfal evacuation, called infemfible tranfpiration. but vifible through a microfcope; and their exiftence is They likewife ferve to tranfmit from without, inwards, Jikewife proved by the cutaneous tranfpiration, and by the fubtle particles or irnprefiions of fome things applied the effefts of topical applications; and from .thefe two fkin. The firft of thefe three ufes depepds on phenomena, they have been divided into arterial and ve- tothetheextremities of the nerves, the fccond on the arterial nal pores. productions, and the third on the productions of tha veins. cutaneous glands fecrete an oily humour of differ-, THE CUTICULA, OR EPIDERMIS. entTjre confiftences, and they are likewife the origin of fweat. The cutfide of the flcin is covered by a thin tranfpa- The epidermis ferves to keep the pencils or nervous firent web, clofely joined to it, which is called epidermis, laments of the papillae in an even fituatiem, and without tuticula, 'Or the fcarf-fkin. confufion.; and it The fubftance of the cuticula appears to be very uni- external objeCts. hkewife moderates the irnpreUions of form on the fide next the /kin, and to be compofed on Another ufe of the epidermis is to regulate the cutathe other fide of a great number of very fine fmaUfqua- neous evacuations already mentioned, the- molt confidermous laminae, without any appearance of a fibrous or vafcular texture, except fome fmall filaments, by which able of which is infenfible tranlpiration. ft is connedted to the papillae. This fubftance is very folid and compadt, but yet ca- THE MEMBRANA^ADIPOSA, AND FAT. pable of being extended aud thickened, as we fee by The fecond univerfal integument of the human body,,