Over and over again the round bit of bismuth and the mass of soft food in which it floated came up to the pylorus as if to demand free passage through. And over and over again, just as often, the soft as well as the hard was positively rejected and sent shooting backwards, only to come again and again to be rejected.

This was kept up until finally the most fluid of the food was refused no longer. It went onward. Later yet the pylorus seemed to give up all protest. It seemed to conclude that there was no hope of ever softening the bismuth. This also was then permitted to go on in company with food which was well prepared for advancement.

From this experiment it is evident that the disadvantage of any hard substance in the stomach is not simply that it is itself slow in passing on through the pylorus, but that it delays the progress of even such food as has already been reduced to chyme-food which should be receiving its next course of treatment in the food tube. The main objection to slow digestion is that after food has stayed too long in the stomach it grows sour and gives off gases which stretch the walls of the stomach and cause distress of various kinds.

The next time you eat in a hurry and are tempted to swallow unchewed lumps of food, think of all this and control yourself in time.

During the X-ray experiments there came an unexpected turn to affairs one day. Thus far Dr. Cannon had

been fortunate enough to have dealings with amiable cats only. They had eaten when he wished, had been quiet and well-mannered during the experiments, and had slept when required. In addition, their stomachs had gone

Food reaches the stomach from the mouth through the oesophagus. While digestion goes on bile runs from the liver directly into the intestine; at other times the opening of the bile duct is shut, and instead of entering the intestine bile passes into the gall bladder, where it is stored until needed. The outline of the pancreas is shown by a dotted line

steadily to work when food was put into them, and had kept ploddingly at it until digestion was accomplished.

But a different type of cat came to Dr. Cannon's hands one morning. This one ate as promptly as the others, and when the X-ray was arranged the shadow showed at

first that the usual regular wave action of the muscular walls was taking place. Suddenly, however, the animal lost his temper. He seemed to feel outraged that anything should be going on which he did not understand. He refused to purr as did the other cats; he insisted on being released. Being in such a state of mind he was useless and had to go. But before he was dismissed it was seen that all the action of the waves had stopped. So much so, indeed, that the stomach was as inactive as if it were empty of food.

This led to close observation of the connection between the feelings of a cat and the behavior of its stomach during digestion. These observations in turn led to the startling discovery that whenever a cat is unhappy or disturbed in its mind by anger, anxiety, or distress of any description, the muscular action of the stomach comes to an end.

To prove this conclusively those who carried on the experiments were obliged to tease a well-disposed cat a little, even while it was under the rays. Before the teasing it purred gently and the wave contractions swept on with rhythmic regularity. But when the teasing began, and when the cat began to feel mental distress and to show it, every wave ceased; the stomach stopped its work abruptly and absolutely. If, then, Dr. Cannon stroked the cat it was at once happy; it purred, and with that purring began again the squeezing and the

monotonous, regular progress of the waves along the walls of the stomach,

Doctors have always known that an unhappy man does not digest his food so well as the same man when he is happy; but none have known just why this is so. It is evident, however, that there is some close connection between happiness and the power of the stomach to keep up the squeezing movement of its waves.

In view of this discovery, nothing could be clearer than the fact that if we wish good work from our own stomachs we must be neither worried, nor anxious, nor angry, either during the time that we are eating or so long afterwards as food is in our stomachs waiting to be digested. For the simple sake of health, therefore, the calm and happy mind is greatly to be desired.

CHAPTER XXII

PURE WATER AND CLEAN MILK

Year after year, for thirty-five years, people died in Pittsburg, Pennsylvania, under the scourge of typhoid fever. As the city grew, the number of deaths multiplied until, during 1907, 622 people died of typhoid alone.

But the misfortune was even worse than this; for besides those who died were the thousands of other people who suffered but did not die. Hundreds at a time, during each month of each year, were ill in their homes and in the hospitals of the city. They lost money because they could not work for daily wages. They paid out for doctors' bills and medicine savings that were intended for food, fuel, clothing, and house rent. Thousands of children were hungry and cold because their parents were too ill to care for them and too weak to work. It is indeed estimated that for each person who dies of typhoid fever eight other persons are ill with it. So matters progressed from bad to worse for thirtyfive years. In the meantime a generation of people came and went. And what was the explanation of this death rate? Just one thing. The drinking-water of