AND PHYSIOLOGY. 



181 



ical and about ^-oiooth of an inch thick, and Chyle Cor- 

 puscles, which are simple cells about eoVoth of an inch in 

 diameter. 



330. The Place where the Chyle enters the Blood. — 

 Principle of Venturi. — As already mentioned the Chyle en- 

 ters the blood through the left Subclavian vein of the neck. 

 It is not, however, simply by the opening of one vessel into 

 another that this is accomplished, but advantage is taken of 

 the union of two currents, so that by their combined force 

 the chyle is drawn in towards the heart. The mouth of the 



Pig. 187. 



Position of the Thoracic Duct and the Veins of the Neck where it empties. 

 S. V. Subclavian Vein. J. Jugular Vein. D. Thoracic Duct. 



Thoracic Duct, however, is provided with valves to prevent 

 the blood from entering it, in case obstruction in the veins 

 should occur. And " it is a physical fact that, when a small 

 tube is inserted perpendicularly into the lower side of a hori- 

 zontal conical pipe, in which water is flowing from the nar- 



Give the size of the Chyle Corpuscles. 330. Give the description of the hydraulic 

 principle by which the chyle is drawn towards the h#art. 



