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Show go Rmnr'fimlians, A/zastomoses, Number, and Size, (iv. declaring that the lymphatics were by no means, in point of number, to be compared with arteries, veins, or nerves; and a physiological writer has Ul'lllCd them a trifling appendage of the red veins. In my dissections, I have found more lymphatics than either arteries or veins, in such parts of the body where I have succeeded well in the injection; and I have no reason to doubt but they are as numerous in the other parts. Tby Situation and Comm (J lbs larger Absorber/t Vessels. 9; with quicksilver, was twice the size of the duct, as it lay behind the root of the lungs, on the spine. Two of the trunks of the absorbents, in the lungs of an ordinary-sized turtle, were each of them as large in diameter as the cava superior in the human subject, and ten times the size of the thoracic duct they belonged to, if the rcceptaculum chyli he excepted. There is in the branches themselves a peculiar appearance, connected In the extremities of the human body, the superficial lymphatics are with their size; this appearance sometimes is to be found in the red veins ; vastly more numerous than the cutaneous veins, fourteen trunks frequently it is then the effect of disease, and we say they are varicose; but it is natural to the lymphatics, particularly in certain parts of the body, and in certain animals. The lymphatics of the legs, liver, and diaphragm, in the human subject, frequently put on this appearance. It is almost always to be found, and that in a very great degree, in the lymphatics of the spleen of a bullock. The vessels appear large at one place, presently contracted to one fourth of that size, and then suddenly dilated again; and thus alter- nately, like a chain of vesicles joined by very small links. accotrtpanying one cutaneous vein: and the deep-seated lymphatics are at least double of the arteries they attend, every artery being commonly ae- companied with two red veins and two lymphatics. On the omcntum of the turtle, the lymphatics are more numerous than the arteries in the pro- portion of four to one; and superior to the veins in the proportion of {our to two; the arrangement being constantly thus: an artery lies in the middle, between two lymphatics; two red veins lie on each side of these last; and two other lymphatics on the outside of the veins. I once injected the lymphatics of the skin by accident; for the mercury ran contrary to the valves. The portion of skin tints injected was small, but the lymphatics were very numerous in proportion; and, from what I then saw, I Could have no doubt of the lymphatics being as nttmerous on the surface of the skin, as they appear on the surface of the intestines. In the arterial system, there is a certain proportion kept up between the CHAP. XVI. TIM Situation and Course (f [be larger Absorbent Vusscls. trunk and the branches; any one of these last being smaller than the trunk, and the branches in general gradually diminishing in size, by branching afresh, in proportion as they rcccde from the trunk. There is a good deal HIPPOCRATES himself seems delighted with the solicitudc of Nature, in contriving a place of the greatest security for the axillary artery, on its of this appearance even in the venous system, though not so regular emerging from the cavity ofthe thoraX,-mI-ni J: waxs'm 3:02 7'11; led©a mvaxn/ throughout; the right jugular, for example, being commonly twice the size of u'mS rfiy dyonAz/rnvr-for this large vessel is placed between the clavicle and scapula, 1;;in 7"? ail-mi yEugou nsgts'xs; armw' 7-7, J; X6V§3@a.-It has a large nerve the cavu superior, its trunk, and the left jugular often twice the size of the left subclavian. But in the absorbent system, the disproportion between the trunk and branches, in point of size, is exceedingly remarkable. I have seen one of the eil'crentia from a gland in the groin larger than any part of the thoracic duct, except its beginning and termination, where it I have seen the trunk of the lacteals equally large. is gent-rally largest. One of the trunks of the lymphatics of the lungs, which I had injected with on one side, and a cartilage on the omen-aid?" d‘s Eéy7©= n3 n'wrs snotty; ,s-aywm ;-for this part having no muscles around it, the vessel otherwise would have been easily tore. Dr. Hunter also, in his Anatomical Lectures, was atmuch pains in pointing out the wisdom of our Author in disposing of the larger arteries and nerves: great part ofthe reasoning he then employed, will apply well here; N 2 but |