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the abdomen of a living animal* is laid open, yet the course of the lymph 

 is far from being as rapid as that of the blood; it even frequently appears 

 affected with irregular oscillations, such as are to be met with in the cir- 

 culation of the blood through the capillary arteries. The numerous di- 

 latations, curvatures and anastomoses of the absorbents must, in a consi- 

 derable degree, impede the rapid progress of the lymph, but the circula- 

 tion must be retarded, chiefly in the glands, as there the vessels are most 

 convoluted, dilated, and form the greatest number of anastomoses, and 

 are most subdivided. Besides, the parietes of the absorbents are thin- 

 nest in their passage through the glands, for, these may be ruptured by 

 the weight of a column of mercury which the vessels themselves are 

 able to support. And the action of these vessels, naturally weaker in 

 that situation, is still farther diminished, by the close cellular adhesion 

 which unites together the vessels whose union forms the glandular bo- 

 dies. 



It was necessary that the course of the lymph should be slackened in 

 its passage through the glands, in order that it might undergo all the 

 changes which those organs are to produce upon it. Although we do 

 not know precisely what those changes are, their object appears to con- 

 sist in a more perfect union and combination of its elements, and in be- 

 stowing on it a certain degree of animalization, as is seen, by the greater 

 tendency to coagulation of the fluid taken from the vasa efferentia. Ano- 

 ther object of the passage of the lymph through the glands, appears to 

 be to deprive it of its heterogeneous particles, or at least to alter their 

 nature, so that they may not become injurious, when they get into the 

 mass of the fluids. The yellow colour of the glands through which the 

 absorbents of the liver pass, the dark colour of the bronchial glands, the 

 red colour of the mesenteric glands, in animals which have been fed on 

 madder or beet root, the whiteness of the same glands, while the chyle 

 is passing through them, are circumstances which show, that the glands 

 separate, or tend to separate, the colouring matter of the lymph, and that 

 if they do not effectually prevent its transmission into the blood, it is be- 

 cause certain colours, as indigo and madder, have too much tenacity, 

 while other substances, as the bile, do not pass through a sufficient num- 

 ber of glands, to lose their colour entirely. The blood-vessels, which 

 are very numerous in the tissue of the conglobate glands, pour into the 

 lymphatics a serous fluid, which dilutes the lymph, increases its quan- 

 tity, and at the same time animalizes it. The number of the lymphatic 

 glands is very great; many are so small as to escape the eye, but become 

 enlarged and visible, in certain cases of disease. I have daily opportu- 

 nities of observing in scrophulous patients, swollen glands, in situations 

 in which anatomists have not pointed out any. The absorbent glands 

 are, at no time, so large nor numerous as in infancy. They very frequently 

 disappear in old people, and it is difficult to say, whether they have been 

 totally destroyed, or whether they are merely exceedingly reduced in 

 bulk. 



* In some cases, the activity of the absorbents appears increased, in a singular de- 

 gree. Tims, jaundice has been known to be the immediate consequence of a wound of 

 the liver; and on other occasions, a metastasis of humours has taken place, with the 

 utmost rapidity. I suspect, that, in such cases, the substance that has been absorbed, 

 circulates by means of the anastomoses, and pervades the lymphatics with which the 

 whole body is covered, but without passing through the glands^ which would slacken 

 its course, and, to a certain degree, alter its nature Author's Note. 



