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Show Eattxii'titu/‘i/s (lit) ‘zs/I‘ali/ig that red Iii/‘11:; (it) not {l/JL‘W'IV. Drprl'immts dciiioristm/i/ig that red Vtvitis do not absorb. 3 In this state, the parts were returned into the ab- " such arguments and experiments, that I dared not, even in my own corresponding arteries. " mind, determine the question." domen; and, by the veins being thus left empty, even a small absorption it: does not appear to have been acquainted with the experiments of Thomas Bartholin, one of the first discovery; of the lymphatics. I find that he had made experiments on the veins of the intestines, in living anL inals, which disproved venal absorption there, and made illll] totally inject it. In the epistle in which he finds fault with Harvey {or rciusing to admit ofthe milk would have been detected, as the coats of the veins are so thin, that they would have permitted a white fluid to appear through their sides cas ingredi, quia nunquam id visum, nuuquam voluit natura, nusqnain patet aditu.‘ re cro non intrare hoe experimentum prohat. Si ligattis sit me- senterieus ranius, non iinpediturchylus, quominus ad lacteas seiisim inde intiiinentcs transeat. At, ligatis lacteis, restitat chylus, nee e ventriculo, aut intestinis, aut lactearum osculis, ulterius progreditur." Mr. John Hunter positively denied the absorption by red veins, and made a number of experiments on living animals, which, in in}: opinion, are. perfectly conclusive: as they are published in his l)1‘t)Li1L' .‘vletlical Commentaries, I shall only give the result. I obsen e, in general, that these experiments were made on the intestines and mesentery of live dillerent animals; several CX1)CI'llIlCHLS V‘i'Cl‘C {1'13- ml tillL‘lni‘Y made in diliercnt parts of the intestinal tube, in each animal, at the, «time time. It has been doubted, whether any experiment, which puts were . aiii allowed to protrude, and carefully examined: the veins were found nearly as empty as when the parts were first returned, and contained not one drop of white fluid; but the lactcals were hill of it. 2d. Similar experiments were made on other animals, with this additional circumstance, that pressure was made on the portions of intestines containKaaw Boerhave imagined, that he forwarded the absorption ing the milk. Alternate and consi- of water, into the veins of the stomach, by pressure. derable pressure was here made, even to that do ‘ee, that at last the intes- tines burst; and yet not a drop of the milk was found in the veins. 3d. It might be objected, that the veins did not absorb, because liga~ tures were made on their trunks: this could he no objection, for the lacIowever, that even teals persist in absorbing under similar circumstance‘. an animal to pain, can he depended on; but there cannot be a doubt of their decisive nature here, for, as the openingr the al )domcn, wounding the the shadow ol~ an objection might be removed, similar experiments to the intestines, and making ligatures on them, (lid 7 not hinder, in the smallest deoree, . {I the ,lactt‘als, l'roni pei'l orming their functions, nor the aiteries and blood continued to circulate, during the whole period. vein s " ioiii ' .. ' Utcllldlltig the. blood, not a shadow of a reason can be given, ' "1]. . ' . . . v) . s - . should not have ‘) the veins absorbe d, supposi' ng them capable ofI tliis olhee. \< x - ' , , 1 st. .l‘.ftti one of thet .animals had been properly secured, and the abdo- nien opened, portions oi the intestines were quickly emptied, bv pressure . ». . V ‘ > . ' ol llitl] I ‘ piopti . tontents, and warm milk was in iected in their place,H and, H q , by. ligatures_. Tl 1L \cius belongi tonhiitd ng to these portions of intestines uttt tniptiti l of ,their blood, ‘ _ by punctures made in their trunks, and pre- ‘ ented (tom receiving' more blood, by ligatures made on the trunks of their t COI‘I‘CS- former were made, where the arteries and veins were left lice, and the After the parts had continued a quarter of an hour in the cavity of the abdomen, they were allowed to protrude again; openings were made in the trunks of the veins, and the blood receiu‘d in vessels; but neither the fluid blood, nor the serum, alter the blood had coagulatcrl, sht‘wed the least mixture of milk. 4th. Similar experiments were made with starch dissolved in water, and Coloured blue with indigo. * Though I have The fluid veual blood did not appear tlarlxer 75ml that a white fluid, mixed with the blood, miglil‘ not be on PW the existence of the lacteals, he says: " Chyltts non potest venas meseria- as readilv as red blood; whereas, had the blood been allowed to circulate through the veins, a small absorption of milk might not, per .aps, be per- ceived, as mixing with much circulating red lluid.* The parts having re» mained in the abdomen a quarter of an hour, half an hour, or more, that the natural warmth oil the cavity might assist the natural absorption, they , the admixture of the chyle, in the left subtlavian min, is on. sily detected, yet, i; '1 perceived, and a " degree ot' milkiness in the serum of coagulated blood .earhly "15* tattered by an .tecusLi ,ed eye. ‘ Ill . ~ i‘W-‘i't- Sigh.,'§,w -‘~ 22 |