DIGESTION. 
the inteftine fae in aie whofe abdomen has been laid 
open, and i who have taken purgative medicines. 
This ir mecley oF he lar ge fein continues after apparent 
death, fo aa to produce even a degree of alvine evacuation 
The longitudinal mufcular fibres, being collected into 
firong bands, and more numerous than in the {mall inteftine, 
act more. powerfully. They are contracted towards - 
appendix vermiformis, in which they all terminate as i 
common centre ; they fharten and dilate the inteftine, clctey 
render it fit to receive the alimentary refidue from the ileum, 
and contribute to its progreffior. 
fibres, when diftended by ceces or flatus, contract an 
it towards the aca. n thus cre 
a 
acviens is perha 
has the frronge® “ealeuae covering. 
large, as in the {mall inteftine, a retrograde or ant'periftaitic 
effect, but it is weaker. “It contributes to the longer reten- 
tion, and more perfe& elaboration of the feces. The reality 
of this antiperiftaltic motion is fhewn by the vomiting of 
clyfters thrown into the reGtum. 
The foeces are gradually colle&ed in the re€tum, which ad- 
mits readily of diftenfion, for which it is particularity adapted 
f the 
ri ftimulating ; the bile fully formed ; 
ecrement itfelf liquid; and the fubje& accuftcmed to eva- 
cuate it on the firlt call, ftools will take place at fhorter in- 
tervals. A coftive flate of bowels will be found in aged, 
weak, and torpid fubjects, in fuch as take moderate 
s, and even months, but the perfons were 
indeed valetudinarians. The ingefta pafs through the whole 
alimentary tube, in from fix to twenty-four hours. If their 
retention exceeds the latter period, fomething unnatural may 
much 
coftive for wee 
the evacuation a s pla 
Evacuation of the Faces. 
This is to a certain nile ig ill in a ney perfon, 
as it sauits of being delayed for fome time Pies when - 
contractions of the re€tum come on pret city rongly, it 
no longer in the power of the will to avoid the expulfion at 
the foeces. The act itfelf ie preceded by a fenfation of fti- 
mulus, ac duli pain in the lower part of the belly, to which 
are added flight fhiverings. This unpleafant feeling excites us 
to employ that effort termed itraining (See RespiraTion); 
and to exert the diaphragm and abdominal mufcles in com- 
bination, in order, by their preflure on the rectum, to over- 
e refiftance of the iphinéter ani, and expel the con- 
tents of ihe re&t The levatores ani fix and fupport the 
gut, and prevent it lias Ries ing too much to this protre- 
five effort. When the ufficiently opened by means 
of this action of the st oa — the re€tum is 
emptied by its own living powers; by the irritabiity of its 
mufcular fibre ef raining is therefore made erated, or 
entirely remitt a 
d of the w When the large ine 
teftine is comp'etely unloaded, the protruded re€tum is re 
ftored to its fituatien, by the levatores ani, affifted by the e 
proper longitudinal fibres of the gut, and the anus is clofed 
by means of its fphin@er. A fenfe ‘of leafare, not only 
in the part, but extending more or lefs over the whole body, 
accompanies the act. = 
Nature and Properties of the Faces. 
Some degree of variaticn in the ee of ov ie 
is compatible with a ftate of health. The be fo fi 
as to have a conglomerated falas probably from being 
formed in the cells of the colon, or fo much fofter as rot 
to preferve this. Longer retention will Tone to that 
appearance, and the fame circum e in excels caufes a 
difeafed ftate of ie evacuations, in which they form hard, 
balls prs pie la. 
Thei 
femble wetted rhubar be 
makes the foeces of a clayey appearance; an 
biliary fecretion will c a 
green, black, &c., all which are mo ie : 
1s influenced, as well as the confiftence, by retention; be- 
The confittence he ild be 
€ excep- 
tions are made to this rule; {pinach is faid to impart a gre a 
and beet-root a red tint to the ftools, il a laa ae 
animal and vegetable matter; hufks of » Kas me 
ranous parts, as fkin of apples, grapes, ie are if Oo ail. 
cerned. ‘Traces of falted or {moked meats are difcovered 
more epee than thofe of recent animal food. 
ftates their quantity at 5 oz. or rather more, when they 
re well f rmeé ike. quantity is greater when they are fluid. 
re more foetid an 
; 4 the 
are taken, the foeces poffefs a fimilar odour 
to that of fete formed from meat or mixed diet. 
tafte js faid to - {weetifh ee and vapid, with fometimes 
an acid admixtu 
Chemical Analyfis. 
In a recent ftate o not affe& vegetable blue infua 
fions: lofe about ice oats of their weight when dried 
upon a water Whe din water, and ftrained 
through linen, a greyifh brown sia remains ; ee 
hen dried ae Se tal rema an ing, in 
qua if to of the li Th € trai liga de- 
oo 
able by the filter, a Rie amo 
coampeles of a fatty matter, Tenuate by Aol, and coil 
dered as the refin of the bile a little altered: s aye sae locke 
ftance diffolved by water, and poflefling the properties of 
gelatine or mucus: and of a greenifh grey refidue, nflube 
in water and alcohol, and leaving, when incinerated, fom 
filica and phofphate of potafh. The liquid that paffed aie 
filter was at firft yellow, then grew brown, and afterwards 
muddy: it contained albumen, bile, a peculiar reddith brown 
fubltance, fuppofed to be refin of bile in an altered ftate, 
and various falts. 
4Ma2 The 
