Other kinds of food, like meat and eggs--which contain no _starch_ and consequently are not acted upon by the saliva--need be chewed only sufficiently long and thoroughly to break them up and reduce them to a coarse pulp, so that they can be readily acted upon by the acid juice of the stomach.
Down the Gullet.

When the food has been thoroughly moistened and crushed in the mouth and rolled into a lump, or bolus, at the back of the tongue, it is started down the elevator shaft which we call the gullet, or esophagus.

It does not fall of its own weight, like coal down a chute, but each separate swallow is carried down the whole nine inches of the gullet by a wave of muscular action.

So powerful and closely applied is this muscular pressure that jugglers can train themselves, with practice, to swallow standing on their heads and even to drink a glass of water in that position; while a horse or a cow always drinks "up-hill." This driving power of the food tube extends throughout its entire length; it is carried out by a series of circular rings of muscles, which are bound together by other threads of muscle running lengthwise, together forming the so-called _muscular coat_ of the tube.
By contracting, or squeezing down in rapid succession, one after another, they move the food along through the tube.

The failure of these little muscles to act properly is one of the causes of constipation and biliousness.