Multiplying, we have 60*40*15 equals 36,000, the number of cubic feet.

This, divided by one thousand, gives thirty-six as the number of seconds.

Thus it appears that with closed doors and windows, breath poisoning of the audience would begin at the end of thirty-six seconds, or less than one minute.

The condition of the air in such a room at the end of an hour cannot be adequately pictured in words, and yet hundreds of audiences are daily subjected to just such inhumane treatment through ignorance." The above remarks apply not only to churches, lecture rooms, and other public places, but also with equal force to offices and family houses.
I should like to know how many persons pay even a little attention to this important subject of pure air breathing?
You go to an office, whether large or small, and you find all the windows closed, although there are half-a-dozen or more persons working in the room.

No wonder that managers, clerks, and other office workers often break down and require a holiday to recuperate their impaired health at the seaside, or elsewhere.
When you call at a private residence you will find the same thing, all the windows closed.