i 8 ) 
df the fame kind, where the Nerves are not expofed, 
unlefs the inverting Membranes, the Dura and Tia 
Mater , be by, any Accident wounded, lacerated or 
corroded ; in which Cafe, the medullary Subrtance 
being laid bare, exquiiite Pain is felt, and very fe- 
vere Symptoms enfue, which are hardly to be over- 
come, or never fo eafily as by cutting the Nerve quite 
through, fo as that the Extremity may retire within 
the FleCh, and the medullary Subrtance be protected 
by it. 
J By which it appears,that the Sides of rhe Nerves are 
infenfible or void of Feeling, and that the Extremity 
of the medullary Subrtance, either by Nature, or by 
Come Accident, laid bare, is the only immediate In- 
ftrttment of Senfation. 
This being premifed, the Stru&ure of the Inte* 
iflines , the Parts in Qu eft ion in the Cafe before us, 
comes to be confidered. 
The IntejHnes are made up of four funics, or 
Coats. 
The firft, or external Coat, is a common mem- 
branous Covering, borrowed of the Peritoneum. 
The fecondis compofed of their annular, contradile, 
mufcular Fibres, the immediate Inftruments of their 
periftaltic Motion. 
The third is the nervous Coat, a reticular Plexus 
of Nerves intermixed with Blood-FeJJels and Glands, 
plac’d immediately under the mufcular, and over the 
villous Coat. 
The fourth is the villous or innermoft Coat, on 
the concave Side, rightly called villous, as it appears 
view’d through a Microfcope ; tho’ from its Appear- 
ance to the naked Eye, it be erroneoufly call’d the mu- 
cous 
