Q. What becomes of the hydrogen of the fuel?
A. Hydrogen (being very inflammable) burns with a blaze, and is the cause of the flame which is produced by combustion. (see p.[34]).
Q. What becomes of the nitrogen of the air, amidst all these changes and combinations?
A. The nitrogen of the air escapes, and is absorbed by the leaves of grass, trees, and various other vegetables.
Q. What is meant when it is said, that oxygen “sustains life”?
A. It means this: if a person could not inhale oxygen, he would die.
Q. What good does this inspiration of oxygen do?
A. 1st—It gives vitality to the blood: and
2ndly—It is the cause of animal heat.