This is not the way to write a book, to force it in a given time, but it was the only opportunity, so was embraced, and here we are at work.

Imagine, if you can, what success we would have if all the time there were this continual gnawing at the stomach that we erroneously call hunger! The thing would be impossible.

Now what we have been talking about is appetite, and in order to distinguish this from hunger let us impress once more that appetite is habit and its resultant accumulation of the acid debris from the last meal eaten, every sensation depending on these two factors always.

Appetite is a creation of habit, wholly, and never a normal thing.

Hunger is the systemic need for food, has no sensations at all except a pleasureable anticipation of eating at some early period, can be deferred without the least discomfort, and expresses itself definitely, as a desire or need for some one specific article of food.

Hunger is never in evidence so long as appetite persists, the disagreeable sensations of appetite covering it up completely, so that we have no way of knowing whether or not we need food till this divorce from the table is quite complete.

The writer has not before fasted for longer than twenty-eight days at any one time, and never in this period did he come to normal hunger, for the fast was always broken because of conditions that seemed to make its further continuance undesirable, but always without real desire for food, nor does he expect to reach normal hunger in this present thirty-one day fast, but some time he expects to go through to the end of a complete fast till hunger demands some one specific thing, and nothing else will do, and only then will he find out what hunger feels like.

Hunger is the announcement of the body that its internal stores of food are exhausted, and there is then instant demand for some one thing that combines those ingredients of which the body stands in immediate need, which the writer has seen three different times expressed as desire for either fried ham or bacon.

These were cases that fasted to the limit, till a normal hunger developed, a fast made necessary by a state of the body that did not permit of slower methods of readjustment, and in all three cases there was a rejuvenation that was truly remarkable.

Mark Twain always leaves his readers to guess just how much of what he tells in his inimitable style is really the truth and how much is merely a good story well told.

In one of his volumes, "The Man Who Corrupted Hadleyburg and Other Stories," he tells of traveling all over his own country seeking a return of a lost appetite, then a sea voyage at the recommendation of his physicians, then travel over much of Europe, still without the lost appetite, and finally his stay at the Appetite Cure at Hochburg House.

Here he was confined to a room, and given a list of foods that he should select his menu from, consisting of the most revolting articles, growing progressively more revolting as the list proceeded, the fifteenth article being "new spring chicken in the shell," and the thirtieth and last being "boiled rubber boot heels."

He was told that he could not consider as first meal any article above the fifteenth, as his case was considered a fairly bad one.

He rang the bell when first it occurred to him that it was time to eat, and ordered some food, no matter what, but was reminded of his diet list, and consulting this he remembered the new spring chicken in the shell and indignantly refused food. Day after day this performance was repeated, all the time approaching the fifteenth article, till on the fifteenth day he surrendered and ordered the disgusting new spring chicken in the shell.

The tray was served by the big boss himself, and as Mark was about to carve the diminutive chicken the proprietor took the tray, announcing that he was now cured, and forthwith brought him a platter of proper food.

Asked how he ever came to adopt such a novel idea for restoring appetite, the proprietor, who was not a physician, told a remarkable tale of shipwreck with a crew of thirty men, and all they could salvage was thirty days' rations for one man, or one day's rations for the thirty men.

They were thirty days from the nearest island by whaleboat, and the captain divided the rations into thirty parts, to each man a thirtieth of one day's rations, and the result was so striking that the man never forgot it, every one on board recovering from all his petty troubles, one a tubercular passenger who had shipped for his health, as they were going around the Horn, another a sailor who had abscesses and boils, but all made the island in good condition. The proprietor said all celebrated their return to food with a gorge that nearly killed them except himself, who had learned to appreciate the fact that the human body needs but a small part of what it takes daily to support it in good working order, and he never again returned to the free and fancy eating habits that are usual the world over.

And so he had conceived this idea of "The Appetite Cure" at Hochburg House, and his fame as a restorer of the joys of eating had spread all over Europe.

It may be but one of Mark Twain's stories, like the jumping frog of Calavaras County, but it is a good story and illustrates just what he probably wished to impress: the bad habits of eating that prevail generally being governed by appetite without allowing hunger any opportunity to decide what is best for the man, when to take this or how much.

There is nothing compelling about hunger, but about appetite there is the greatest compulsion, the dreadful gnawing sensation driving one to eat almost anything that is offered, even civilised, men eating each other when driven by this compelling desire or goaded on by their atavistic fear of starvation.

It is nothing but atavistic, no doubt handed down by our remote ancestors from times when food was all important as the one means of sustaining life, and the supply very precarious.