preferves Part of the Fluid in each Fold to raise Steam. At the low End of the Ilium, and upper End of the Colon, there is a Valve placed, fo that nothing can país but when it is opened. As the Excrements or Mash fettle lower, the Fluids go off in Steam, and the Remainder becomes ftill lefs and lefs Fluid. Contraction, or Distention, 'tis likely has leaft Effect in the two upper Parts, because they are mostly empty, or their Contents are very thin, unless fome Stop by Phlegm or, &c. happen. But perhaps in the Folds of the two lower, where the Excrements are lefs fluid, the Bags may contract fo far as to hinder the Steam from paffing through them, till Juices fecrete, raife a new Ferment, and re-extend them. If the Cacum, and the low End of the Ilium, next the Valve at the Top of the Colon, be filled with thick Excrements, when there is no Steam in them, or below fufficient to refift, the Steam above will prefs upon them, and push or thrust them forward with a great Force. If the Guts were all of one Wideness, and not fo bended and girt with Strictures, the Fluids would run down to the next Stop or Valve, make no Stay in the upper Parts, fill the lower End, and leave the

upper

upper End empty. As they are contrived when the Pilorus opens, and the Steam and Fluids go off from the Stomach, they will extend the Bags as they go, fill the first Bag first, and when that is full, the Fluid will run over the Bend, or Stricture to the next, and fo fill each fucceffively as more Fluid goes off. If the Guts had a ferpentine Winding, or Peristaltick Motion conftantly, it must be performed by the Steam driving the Blood along the Arteries, at each Push, moving the Guts as it paffes the Arteries in their Sides, which Blood must be repelled along the Veins in the Sides of them, by the Ex, pansion of the Steam within the Guts, and the Refiftance of the Infides of the Trunk, or if they only had fuch a Mọtion fometimes, it might be performed by the Motion of the Steam, when the PiLorus opens, iffuing from the Stomach downwards, and the Fluids along with it, and fo on after the Guts are filled with Steam, as it gets Vent: But if there were fuch Motions, they cannot be fufficient for discharging the Excrements out of the feveral Bags and Folds, and at laft out of them at the Fundament; nor do I think it poffible, that the Guts can have any Peristaltick Motion, because they, &c. fill

the

fill the Trunk close, and have no Room to move and fhift in, otherwise than as the Steam abates in one Part, and encreafes or extends in another; the one Part will be compreffed, the other extended, and nothing can defcend, or be emptied downward out of the Bottom of the Stomach, or the Bags of the Guts, but by their being lifted up to the Level of the Pilorus of the Stomach, or the Tops of the Bags, or Strictures in the Guts. When the Stomach begins to discharge into the Guts, it fills them, and extends them: by their Ferment as they fill and extend, the Refiftance in the Stomach being leffened, they lift up its Bottom, and by Degrees empty it, as the lower Parts of the Guts fill and extend with the Ferment and Steam; and as it abates in the upper Parts, they lift up the Bottoms of the Bags in the upper Parts, and difcharge the Fluids downward fucceffively to the Colon, which feems to be another Repofitory for the Excrements, wherein 'tis likely they undergo fome farther Fermentation like a fecond Stomach; but differs in feveral Refpects. It has lacteal Veffels out of it to carry off the Steam when there is a Ferment in it. When it is extended with Steam, it lifts up the Bags

Bags in the Guts above it, and makes them empty downwards towards it, and when the Valve at its Top opens, which perhaps is when the Steam in it abates, the Excrements at the lower Ends of the Guts above will fall, or be preffed into it. Whether the Bags in the Guts, or the Valve at the Top of the Colon, always keep Fluids in them to raise Steam, and keep them fomewhat extended, I am not certain; but if they ever make a fudden Discharge into the Colon, and the Steam in them be much weakened, perhaps they may contract, and their Glands be ftocked with Juices to raise a new Ferment in the next Supply; and the Colon during the Time the Steam in it was weak, would replenish its Glands with Juices to raise a new Ferment, and fupply the lacteal Veffels with Steam; whilst that in the Guts is weakened. And whether when fuch a Discharge is made into the Colon out of the Guts, or the Fluids are mostly born off, and the Steam weakened there, and the Steam in the Stomach be ftrong or ftronger than that in the Guts, it may not contribute to open the Pilorus, and give the Steam and Mash Paffage into the Guts, I cannot tell.

When

ner of the

The Man- When as much of the Mash has paffed Excre- one of the Stops that the Steam above is ments be- abated, the Valve fhuts by the Preffure ing pufh'd upon the Blood within the Colon, refts or down and evacuated. leans upon the Loins flanting, fo that when the Fermentation in it is over, and

the Steam abates, the Preffure of the Steam in the Guts above, forces the Excrements in it downward. Whether the Fermentations in the feveral Parts are carried on by the Juices iffued out of the Sides of the Stomach, or they are renewed or affifted by Juices iffued out of the Sides of the feveral Parts of the Guts, or by the Gall and Pancreatick Juices, or whether there is always as much fermented Fluid left in the Bags of the Stomach, Guts, and Colon, as will contribute fomething like Leaven, to raise a new Ferment in the next Supplies of Meat and Drink, and whether, the longer they continue there, the ftronger they may grow for that End, in defect of Juices being fecreted out of the Blood, I undertake not to determine. The Rectum reaches straight from the Bottom of the Colon to the Valve at the Fundament, there is no Valve at its Top, because I think as the Excrements are generally pretty thick there,

they