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what knowledge we have of the minute diftributlon 
of thofe veflels in quadrupeds has been acquired from 
examining them when filled with their natural fluid, 
the chyle j for the valves with which thofe veflels 
abound prevent our injeding their fmaller branches ; 
as we do thofe of the arteries and veins of the in- 
teftines.- But in this animal, I have been fo fortu- 
nate as to force the valves, and to injedt the ladleals 
from their trunks to their branches, fo as to fill them 
all around with quickfilver, in feveral parts of the in- 
teftine. In thefe experiments I obferved, that the 
quickfilver was often flopped by the valves, where the 
ladleals run upon the mefentery, or where they are 
juft leaving the inteftine j but when thofe valves were 
forced, and the quickfilver had once got upon the 
furface of the gut, it generally ran forward without 
feeming to meet with any obftacle. The ladleals 
anaftomofe upon the inteftines, fo that the quick- 
filver, which has got upon them byoneveffel, in ge- 
neral, returns by another, at fome diftance. The 
larger ladteals, which run upon the inteftines, ac- 
company the blood-veflels ; but the fmaller ladteals 
neither accompany thofe veflels, nor pafs in the fame 
diredtion, but run longitudinally upon the gut, and 
dip down through the mufcular coat into the cellular 
or nervous, as it has been called, which in this ani- 
mal is very thin in comparifon to what it is in the 
human fubjedt. So far I have traced thofe veflels to 
my fatisfadlionj but what becomes of them after they 
have got to the cellular coat is not fo eafy to deter- 
mine : in five or fix different experiments which I 
have made, the mercury paffed from the ladleals into 
the cells between the mufcular coat and the internal, 
and 
