6o The Art of Farriery 



continues for fome Time after the Full and Change : 

 And though the Aftion of the Luminaries fhould 

 ceafe, the Flux and Reflux of the Sea would, for 

 fome Time, continue. 



Now, did the Blood conftantly move forwards 

 with the Motion at firll communicated to it, and 

 did the Coats of the Veflels make no Refillance, 

 the. Pofterior Blood would not be retarded or hindered 

 by the Anterior; or the Blood, thrown out of the 

 Heart by the Contraction of the Left Ventricle, 

 v/ould not be retarded in its Motion by the Blood 

 already in the Aorta or great Artery ; and the. 

 Force of the Blood would equal the entire Force 

 of the Mover. But, becaufe of the Refillance 

 made by the Coats of the Arteries and Veins,, 

 and the Force which is fpent in diftending them, 

 the Bloood is continually retarded in its Motion 

 as it circulates, and would,, in a fhort Time, 

 ftop, were not the loft Motion made up by a frefli 

 I'mpulfe from the Heart ; and therefore the Force 

 of the Heart, mull be equal to the Rcfiflances the 

 Blood meets with in its Motion : If it were more, 

 the Velocity of the Blood would be continually in- 

 creafing; iflefs, it would continually decreafe, and 

 at lafl flop. And from hence it is evident, that if 

 the Circulation of the Blood was once flopped, all 

 the Force of the Heart could never fet it a moving 

 again. I fhall now proceed to fhew how, and in 

 what Way, the Circulation of the Blood is per- 

 formed, in a more particular Manner tlian I have 

 yet done in my Defcription of the Heart, t^c 



■ To form a right Apprehenfion of the Animal CEco- 

 nomy, it is of the utmofl Confequence thoroughly 

 to underftand the Circulation of the Blood ; for befides 

 what I have faid under the Titles, Blocd, Syllole, Di- 

 aflole, and Aorta, it may be proper farther to take No- 

 tice here, and fhew what is meant by an Artery, and ' 

 afterwards, what is underllood by a Vein : For really, 

 moll Farriers are fo very ignorant, that they are in 

 i\iQ Dark, with Relation to this fo necelTary Piece of 



Knowledge, 



