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Show Experiments n'rmmzsfmliug that red V43in: do not absorb, Ezra/ir‘wzi/s tic/rims!rating tb/ll red Veins do not absorb. way than by the been, unless they had got into the blood by some other nt, that the experime from know, we but duct: thoracic the lacteals and a tenth part of quantity of fluid fixed on will easily pass through a tube of no other force an inch in diameter, in any of the periods assigned, though hoc ipsum phaenonienon occurrit mihi szepius in mesentcriis valde anomarum anicularnm-Conira vero aperienti cadavcra eorum q‘ll in llore ectatis occubnerant, appartiit mesentcrium refertnm tanta glandularum copia, tit in portionc cjuspalnne mantis mquali, sexagiiita vcl septuaginta'glan- a syringe. be applied than that commonly exerted in throwing water through dulas invcncrim,"-l"rom th se circumstances he is disposed to draw the strong reasons for As to the velocity of the absorbed fluids, there are very following inference: " Scd quid tum cliylo contigit qui salelmt prius per venas lactcas deferri ad has in mescnterio glandulas, eertos ct necessarios in usus? Ibitne forsitan ille jam per ventilas mcscntericas cxiguas ct intesti- norum cavis absorptus in ipsnm hepar 9" Haller says, " Dudum sc absque lactcis vivcrc Riiyscliius solebat dicere." To this argument I reply, that all the solids shrinl; in old people; some, however, in a greater proportion than others, as we see in the breasts of 30 the believing it to be diii‘ercnt at diderent times. No man can tell why absorbents should have their orifices immersed in the fluid of ascitcs for months or years, without taking up any sensible part of it; and why, on some stimulus from the constitution, they should remove it in three day . this, however, has sometimes happened; it happened to one of Dr. Hunter's medical l‘riends, as he informed us at lectures; and it has happened to 31 others. The chyle in the lacteals of the mesentery of dogs, in some of my experiments, evidently run through a space of four inches in a se- exceeding- women. It cannot be denied, the glands of the mesentcry are that they are ly small in old people; but it does not necessarily follow, eond, which is 20 feet in a minute: I have at other times seen the ab- sorbed lhlid‘s vanish with almost incredible velocity: so that little can he clnle in old entirely obstructed. I have sometimes seen the lacteals full of full of people. Hallcr says, that he has frequently seen the thoracic duct chyle, in those who had passed the 70th year of their age: " In scnibus," says he, " non raro, ductum thoracicum chylo albo plenum reperiissem." concluded on, against the possibility of the fluids mentioned being absorbed by the lacteals, or transmitted by the thoracic duct, within the assigned pew The diameter of the thoracic duct, in the middle d'ihe back, obstructed ; This could not have happened, if the lactcals had been totally where it is narrowest, is very often double that which Haller has fixed as the mesenteric veins do not lead to that duet, nor has it any other species has been of vessel coming to it from the mesentcry.--ln the last place, it when done, have should they as quickly so died not have said, that animals supposing the thoracic duct was either tied, tore through, or obstructed, From itto be the only road by which the chylc could get into the blood. riods. on. Sometimes there are two thoracic ducts, with separate insertions into the veins. There is constantly a trunk in the anterior mediastiiium, under the sternum, as large as the thoracic duct itself, which is sometimes inserted into the termination ofthe thoracic duct, sometimes into the trunk of the absorbent: of the right ride, and which I have seen transmitting the chylc.- Ruysch has supplied the supporters ofabsorption by red \‘Cins with another argument. Hc asserts, that the lymphatic glands, on the inescnterics of old people, are almost entirely obliterated; and, as he belicvul that all the lacteals went to those glaiv 3, if they disappeared, the lactcals must also he obliterated or obstructed: but, as old people frequently enjoy, under such circumstances, very good health, he could not help believing, that in them the red veins of the intestines performed the oihec of the lactcals. His words are: " Nam in spatio meserxi, palmam mantis aequante, duas (glan- (lulusy tantuin rcpcricbam, aut tres, seminc caniiabino vix iiizijtii'es. Att lie of the Academy of an experiment of Duverney‘s, related in the Memoirs wins, into which the after days fifteen lived do}; tliata pears Sciences, it fiartholin mentions a case where the thoracic duct is inserted, were tied up. g, the patient lived a the thoracic duct was wouirdtrl, whci‘t‘, notwithstandin Mr. (‘licston, of ilis words arc, "longa lizii tahes." considerable time. duct from the ihoracxc the London in its shewcd ago, Gloucester, some years . . \ V i . - \ . I x, -' , . . l ' S‘lbrldHLL) \.lnth had (\tly .htinian subJeci, tttal‘y (11‘ iiucttd with a solid \ ‘ those Allowing, time. , :ttl there {or a long , 4; renizi' .. I t . . t: of he .."pric‘if'tr‘g s or lac- . the lvmphatic P ‘ s‘ their full tor ' thcv4 by- no _means Aprove that ai‘n‘unicnt D lhc thoracic sels. blood-ves the \nto matter nutrit‘ous [this did not carry duct hos |