'304 OF THE CIRCULATORY SYSTEM. SECT. XXIII. i. 

 SECT. XXIII. 



OF THE CIRCULATORY SYSTEM. 



I. The heart and arteries have no antagonift mufcles. 

 Veins abforbtbe blood, propel it forwards, and di/tcnd 

 the heart ; contraction of the htart diftends the ar- 

 teries. Vena port arum. II. Glands which take their 

 fluids from the blood. With long necks, with fljort 

 necks. II], Ahforbent fyjlem. IV. Heat given out 

 from glandular fecretions. Blood changes colour in 

 the lungs and in the glands and capillaries. V. Blood 

 is abforbed by veins, as chyle by lafteal veffels, otber- 

 ivife they could not join their ftreams. VI. Two kinds 

 offtimulus, agreeable and difagreeable. Glandular 

 appetency. Glands originally poffejjed fenfation. 



I. WE now ftep forwards to itluftrate fome of the 

 phenomena of difeafes, and to trace out their mod 

 efficacious methods of cure ; and (hall commence 

 this fubjeft with a fhort defcription of the circulatory 

 fyftem. 



As the nerves, whqfe extremities form our various 

 organs of fenfe and mufcles, are all joined, or com- 

 municate, by means of the brain, for the convenience 

 perhaps of the diftribution of a fubtile etherial fluid 

 for the purpofe of motion ; fo all thqfe veflels of the 

 body, which carry the grofler fluids for the purpofes 

 of nutrition, communicate with each other by the 

 heart. 



The heart and arteries are hollow mufcles, and 

 are therefore indued with power of contraction ir^ 

 confecjuence of ftimulus, like all other mufcular 

 fibres ; but, as they have no antagonift mufcles, thq 

 cavities of the veifels, which they form, would re- 

 main 



