THE STORY OF DIGESTION 53 



by the liver. At the close of digestion the food, 

 which receives the name of chyle (it is called chyme 

 when it leaves the stomach), must therefore consist 

 largely of fats, and this is found to be really the case. 

 The chyle is a fluid resembling milk in appearance. 

 It is absorbed from the intestine by a delicate series 

 of vessels which take their origin in little projections 

 on the walls of the intestine called villi. Passing 

 through the cells forming the outer wall of these 

 projections, the chyle is conveyed by the absorbent 

 vessels already mentioned to a tube termed the 

 thoracic duct (Fig. 12) lying on the left side of the 

 spine. Received into this tube, the chyle is passed 

 upwards, and ultimately we find the thoracic duct 

 ending in a large vein at the root of the neck on the 

 left side (Fig. 12). At this point we may regard in one 

 sense as situated the junction between the food and 

 the blood. The absorbent system of vessels, however, 

 has other duties to discharge in addition to that of 

 bringing chyle from the digestive system to the blood. 

 All through the body we find delicate absorbent 

 vessels termed lymphatics (Fig. 13). They are found 

 to carry a clear fluid known as lymph. This fluid 

 really represents colourless blood, and the lymphatics 

 receive this lymph as the overflow of the blood which 

 has escaped from the finest bloodvessels of the body 

 so as directly to nourish the most minute structures 

 of the body. As the absorbent vessels carry this 

 lymph back to the thoracic duct and to a smaller 

 and neighbour duct situated at the right side of the 

 spine (Fig. 12), the ultimate destination of the lymph 

 is seen to be the blood current, and into the blood 

 stream it is ultimately poured. The body is thus 

 seen to be nourished from two sources, first from 

 the food we eat, and second from the lymph, which, 



