554 
ON THE LYMPHATICS* 
they did not, and that there was no passage for liquors between 
an intestine and the mesenteric veins, otherwise than by trans¬ 
udation*. But authors of the best credit had given such argu¬ 
ments and experiments in favour of absorption by veins, that I 
dared not, in my own mind, even determine the question. At 
this time my brother was deeply engaged in physiological in¬ 
quiries, and in making experiments on living animals, and in pro¬ 
secuting comparative anatomy with great application and accu¬ 
racy. It is well known that I speak of him with moderation 
when I say so. He took the subject of absorption into his consi¬ 
deration ; and from his observations was inclined to believe, that 
in the human body there was owe, and but one , system of vessels 
for absorption. He knew so well that many things had been 
asserted by one person after another, which were not true, and 
so many mistakes had been made from inattention, so many 
errors introduced from other causes, that he could easily suppose 
the veins might not, perhaps, absorb, after all the demonstra¬ 
tions that had been given of the fact, and therefore was deter¬ 
mined to see how far this point could be cleared up by plain ex¬ 
periments and observations^.” 
From the time of Mr. J. Hunter to the present, and more par¬ 
ticularly in this country, it has been held and taught as a gene¬ 
rally received opinion, that in the living body there are three 
orders of vessels, viz., arteries, veins, and absorbents; and it has 
been again admitted, and which is a well known fact, that the 
lymphatic vessels, as well as taking their origin from surfaces, 
&c., likewise arise from the extreme branches of the arterial sys¬ 
tem, as had previously been asserted by Nuck, Cowper, &c. For 
a further proof of this, I shall introduce some important cases 
which occurred in the College very shortly after I first discovered 
* From my own injections and experiments I am ready to prove that 
the mesenteric veins, as well as arising from the arteries, also arise from 
Ihe whole internal surface of the intestinal canal, by open mouths; and there 
are seen by injecting the veins first, and the arteries afterwards, with yellow 
and red injection, and the mouths of the veins appear almost as numerous 
as the terminations of the arteries. 1 am not of opinion that Ihe mesenteric 
veins have any share in the absorption of the chyle; but I have not the least 
doubt that they have a very great share in the absorption of the other fluids, 
&c., belonging to the intestinal canal. I find, also, that the veins arise by 
open mouths from the external surface of the shin, almost or quite as nume¬ 
rous as the arteries terminate; and a similar thing is to be seen on the ex¬ 
ternal surface of the chorion, or that portion which, in the living state, is 
attached to the cellular substance that forms the placenta. This is a state¬ 
ment of facts which the follow ers of Dr. and Mr. J. Hunter will never be 
able effectually to overthrow. 
f Dr. Hunter’s Medical Commentaries, part i, page 41. 1762. 
