20 parts
Carbonic acid
58 "
Oxygen
3.5 "
Nitrogen
18.5 "
"Until 1864 it found no practical application, except as a homeopathic remedy for headache, similar to those which it causes. In that year, Alfred Nobel, a Swede, of Hamburg, began its manufacture on a large scale, and, though he sacrificed a brother to the terrible agent he had created, he persevered until in its later and safer forms nitro-glycerine has come into wide use and popularity. It is a clear, oily, colorless, odorless, and slightly sweet liquid, and can, with safety, only be poured into some running stream if one wishes to be rid of it. Through the pores of the skin, or in the stomach, even in small quantities, this oil causes a terrible headache and colic, while headaches also result from inhaling the gases of its combustion. It has thirteen times the force of gunpowder, exploding so much more suddenly than that agent does, that in reality it is much more powerful, and it is this same rapid explosive power that prevents it from being used in fire-arms."
"You would make a first-rate professor, George," said Ralph, laughing, "and you may refer to me in case you should desire to procure such a position. Now I think I am armed with sufficient knowledge to be able to meet your oily friends, the moonlighters, and have some idea of what they mean when they speak."
"If I am not mistaken we shall meet some of them very soon, without trying hard; but if we do not, I will take you to one of their cabins as soon as we may both feel inclined to go."