36 



fcrent animals receive different fubftances as food ; 

 as, the horfe, grain ; the dog, flefli ; and this gives 

 feme variety to the organs of each. The food is ga- 

 thered by the front teeth; it is then maflicated, or 

 chewed, by the gri/iderSj which are wifely placed 

 far back in the mouth, where, as being near the cen- 

 tre of motion, they have more power ; and, as all 

 griLding is affiftedby moiCiure, falivay or fpi file, is pour- 

 ed forth into the mouth. The food being rendered 

 fmall and moifl, pafTes into a bag called the. JlojnacHf 

 where it becomes ftill farther diffolved and adted on ; 

 which procefs is called digejlion. 



Some animals carry on their digefiion in more 

 Jlomachs than one. Oxen and fheep live wholly on 

 herbage, which, affording }efs nourifhment than grain, 

 or flefli, they have need of more extenfive organs to 

 digefl what they eat, very completely. An ox firfl 

 colleds a quantity of grafs, which, as he fwallows, 

 pafTes into a membranous bag called the paunch : 

 when this is filled, he lays down, and then has a 

 power of bringing the pulpy mafs up again to rechew 

 it, and mix it with more faliva ; when it is direded 

 into a fecond flomach, without again entering the 

 firfl, or paunch ; from whence it paffcs on to a third, 

 and a fourth. The horfe, the afs, the hog, and the 

 dog, have one flomach only; but in the horfe this 

 organ is of a different kind, in fome rcfpeds, to that 

 of mofl other quadrupeds, except affes, rats, and 



