VASCULAR SYSTEM. 119 



the anastomosing branches: cut off a dead man's arm, in- 

 sert a tube in the brachial artery, place the other end of the 

 tube in the carotid artery of a dog, and the artery in the 

 wrist will be felt: no animal has arterial pulsations except 

 those with hearts, or with a vascular arrangement giving 

 an impulse as the heart does: lastly, the fatal consequences 

 of independent arterial action must be at 'once evident. 



Q. Where does the power of the heart over the blood 

 cease? 



Jl. In the capillaries, where it changes from red to black 

 blood; it diminishes sooner, but is lost there. 



Q. With what textures should the arteries be classed ? 



ft. With the cartilaginous, fibro-cartilaginous, and 

 fibrous textures. 



Q. What moves the blood in the capillaries? 



J3.. The branches are so minute that insensible organic 

 contractility or tonicity is sufficient to move it. 



Q. What are the causes chiefly affecting the pulse? 



#. The increase of the sensible organic contractility of 

 the heart ; alterations in the quality of the blood render- 

 ing it more or less irritating to the heart; obstructions in 

 the capillary system; all these produce variations in the 

 conditions of the pulse. 



Q. Are the sympathies of the arterial texture numer- 

 ous or active? 



*ft. The obscurity of arterial vital properties would 

 answer negatively. , , 



Q. How do the vital properties of organs generally in- 

 fluence sympathy? 



Jl. Sympathies depend on vital properties; mechanical 

 or textural properties have capacity neither to radiate nor 

 receive sympathetic impressions. 



