_Oesophagus_, or _Gullet_.--This tube extends from the mouth to the stomach, and is the medium through which the food is conveyed to the latter organ. This tube is furnished with spiral muscles, which run in different directions. By this arrangement, the food ascends or descends at the will of the animal. The inner coat of the gullet is a continuation of the same membrane that lines the mouth, nostrils, &c. The gullet passes down the neck, inclining to the left side of the windpipe, until it reaches the diaphragm, through a perforation of which it passes, and finally terminates in the stomach. The food, having undergone a slight mastication by the action of the teeth, is formed into a pellet, and, being both moistened and lubricated with saliva, passes down the gullet, by the action of the muscles, and falls immediately into the paunch, or rumen; here the food undergoes a process of maceration, or trituration. The food, after remaining in this portion of the stomach a short time, and being submitted to the united action of heat and moisture, passes into another division of the stomach, called _reticulum_, the inner surface of which abounds in cells: at the bottom, and indeed in all parts of them there are glands, which secrete from the blood the gastric fluids. This stomach possesses a property similar to that of the bladder, viz., that of contracting upon its contents. In the act of contracting, it squeezes out a portion of the partly masticated food and fluids; the former comes within the spiral muscles, is embraced by them, and thus ascends the gullet, and passes into the mouth for remastication. The soft and fluid parts continue on to the many plus and true digestive stomach. The second stomach again receives a portion from the paunch, and the process is continued. Rumination and digestion, however, are mechanico-vital actions, and can only be properly performed when the animal is in a healthy state. Now, a portion of the food, we just observed, had ascended the gullet by the aid of spiral muscles, and entered the mouth; it is again submitted to the action of the grinders, and a fresh supply of saliva; it is at length swallowed a second time, and goes through the same routine as that just described, passing into the manyplus or manifolds, as it is termed.