“Then a man, in traveling, ought to know the water supply of every city he goes to. How is he to find out?”

“In your case, Mr. Clyde, he’s to find out from his Chinese doctor,” said the other smiling. “I’m collecting data from state and city health boards, on that and other points. Air will now come in for its share of attention.”

Young Manny Clyde grinned. “What’s the use, Dr. Strong?” he said. “Nothing to breathe but air, you know.”

“True enough, youngster; but you can pick your air to some extent, so it’s worth while to know where it’s good and where it’s bad. Take Chicago, for instance. It has a very high pneumonia rate, and no wonder! The air there is a whirling mass of soot. After breathing that stuff a while, the lungs lose something of their power to resist, and the pneumococcus bacillus—that’s the little fellow that brings pneumonia and is always hanging about, looking for an opening in unprotected breathing apparatus—gets in his deadly work. Somewhere I’ve seen it stated that one railroad alone which runs through Chicago deposits more than a ton of cinders per year on every acre of ground bordering on its track. Now, no man can breathe that kind of an atmosphere and not feel the evil effects. Pittsburg is as bad, and Cincinnati and Cleveland aren’t much better. We save on hard coal and smoke-consumers, and lose in disease and human life, in our soft-coal cities. When I go to any of them I pick the topmost room in the highest hotel I can find, and thus get above the worst of it.”

“Don’t tell me that New York is unfit to breathe in!” said Mrs. Clyde, with a woman’s love for the metropolis.

“Thus far it’s pretty clean. The worst thing about New York is that they dry-sweep their streets and throw all the dust there is right in your face. The next worst is the subway. When analysis was made of the tube’s air, the experimenters were surprised to find very few germs. But they were shocked to find the atmosphere full of tiny splinters of steel. It’s even worse to breathe steel than to breathe coal.”

“Any railroad track must be bad, then,” said Mr. Clyde.

“Not necessarily. A steam railroad track runs mostly in the open, and that great cleaner, the wind, takes care of most of the trouble it stirs up. By the way, the cheaper you travel, the better you travel.”

“That sounds like one of those maxims of the many that only the few believe,” remarked Mrs. Clyde.

“You won’t practice it, but you can safely believe it,” retorted the doctor. “The atmosphere in a day coach is always better than in a parlor car, because there’s an occasional direct draft through. As for a sleeping-car,—well, I never get into one without thinking of the definition in ‘Life’s’ dictionary: ‘Sleeping-Car—An invention for the purpose of transporting bad air from one city to another.’”