92 



The nutriment then pursues its way through ths 

 mazes <>f the intestines : which by a worm-like mo- 

 tion protrude it and force its small particles into the 

 lacteal Kfsscls. These are a series of the finest 

 5trai ers, ranged into countless multitudes all along the 

 sides of the winding passage. Had this been strait or 

 short, the food could not have resigned a sufficient 

 quantity of its nourishing particles. Therefore it is 

 artfully convolved and greatly extended, that whatever 

 passes may ' be sifted thoroughly. As the aliment pro. 

 ceeiis, it is more and more drained of its nutritious 

 juices. In consequence of this, it would become hard, 

 and pain the tender parts, but that glands are posted 

 in proper places, to discharge a lubricated fluid. 

 These are smaller or fewer, near the stomach, because 

 there the aliment is moist enough : whereas in the 

 bowels remote from the stomach, they are either multi- 

 plied or enlarged. 



The Chyle drawn off by the lacteals is carried 

 through millions of ducts, too fine even for the micro, 

 scrope to discover. To this it is owing, that nothing 

 enters the blood, but what is capable of passing 

 through the finest vessels. It is then "lodged in seve- 

 ral commodious cells (the glands of the mesentery) 

 and there rnixt with a thin diluting lymph, which 

 makes it more apt to flow. Hence it is conveyed to 

 the common receptacle, and mounts' through a per. 

 pendicular tube into the left subclavian vern. This 

 tube lies contiguous to the great artery, whose strong 

 pulsation drives on the fluid and enables it to ascend 

 and unload its treasure, at the very door of the 

 lieart. 



But the chyle is as yet in too crude a state, to be 

 fit for the amm 1 functions. Therefore it is thrown 

 into the lungs. In the spungy cells of this casing 

 laboratory, it mixes v*ith the external air ; and its 

 whole substance i& made more smooth and uniform. 

 Thus improved i! nt.ers the left ventricle of the heart, 

 a strong, active indefatigable muscle. The large mus- 

 cles of the aria or of the thigh are soon wearied: a 



