VESSELS OF ANIMALS. 116 



dia o»* orifice by which it enters ; so that it is by the con- 

 traction of the muscular coat of the stomach that the con- 

 tents, after having undergone the application of the gastric 

 menstruum, are gradually pressed out. In dogs and cats, 

 this action of the coats of the stomach has been displayed 

 to the eye. It is a slow and gentle undulation, propagated 

 from one orifice of the stomach to the other. For the same 

 reason that I omitted, for the present, offering any observa- 

 tion upon the digestive fluid, I shall say nothing concerning 

 the bile or the pancreatic juice, further than to observe upon 

 the mechanism, namely, that from the glands in which these 

 secretions are elaborated, pipes are laid into the first of the 

 intestines, through which pipes the product of each gland 

 flows into that bowel, and is there mixed with the aliment 

 as soon almost as it passes the stomach ; adding also, as a 

 remark, how grievously this same bile offends the stomach 

 itself, yet cherishes the vessel that lies next to it. 



Secondly, we have now the aliment in the intestines 

 converted into pulp ; and though lately consisting of ten dif- 

 ferent viands, reduced to nearly a uniform substance, and to 

 a state fitted for yielding its essence, which is called chyle, 

 but which is milk, or more nearly resembling milk than any 

 other liquor with which it can be compared For the strain- 

 ing off' this fluid from the digested aliment in the course of 

 its long progress through the body, myriads of capillary 

 tubes, that is, pipes as small as hairs, open their orifices into 

 the cavity of eveiy part of the intestines. These tubes, 

 which are so fine and slender as not to be visible unless 

 when distended with chyle, soon unite into larger branches. 

 The pipes formed by this union terminate in glands, from 

 which other pipes, of a still larger diameter, arising, carry 

 the chyle from all parts into a common reservoir or recep- 

 tacle. This receptacle is a bag of size enough to hold about 

 two table-spoonfuls ; and from this vessel a duct or main 

 pipe proceeds, climbing up the back part of the chest, and 

 afterwards creeping along the gullet tiU it reach the neck. 



