I noted also that most of the buildings are built against a hillside or surrounded by heavy mounds of earth, so that if one of them blows up, the others may be protected against the flight of debris. Without such barricade the shattered walls and rocks would be hurled in all directions with the energy of cannonballs, and a single explosion would probably mean the destruction of the entire works.
At one place I saw a triangular frame of timbers and iron supporting a five-hundred-pound swinging mortar, that hung down like a great gipsy kettle under its tripod. In front of this mortar was a sand-heap, and here, I learned, were made the tests of dynamite, a certain quantity of this lot or that being exploded against the sand-heap, and the mortar's swing back from the recoil giving a measure of its force. The more nitroglycerin there is in a given lot of dynamite, the farther back the mortar will swing. It should be understood that there are many different grades of dynamite, the strength of these depending upon how much nitroglycerin has been absorbed by a certain kind of porous earth.
In a little white house beyond the laboratory I found the superintendent of the works, a man of few words, accustomed to give brief orders and have them obeyed. He did not care to talk about dynamite—they never do. He did not think there was much to say, anyhow, except that people have silly notions about the danger. He had been working with dynamite now for twenty-five years, and never had an accident—that is, himself. Oh, yes; some men had been killed in his time, but not so many as in other occupations—not nearly so many as in railroading. Of course there was danger in dealing with any great force; the thing would run away with you now and then; but on the whole he regarded dynamite as a very well behaved commodity, and much slandered.
"Then you think dynamite-workers have no great need of courage?" I suggested.
"No more than others. Why should they? They work along for years, and nothing happens. They might as well be shoveling coal. And if anything does happen, it's over so quick that courage isn't much use."
Having said this, he hesitated a moment, and then, as if in a spirit of fairness, told of a certain man at the head of a nitroglycerin-mill who on one occasion did do a little thing that some people called brave. He wouldn't give the name of this "certain man," but I fancied I could guess it.
"HE WENT TO WORK THROWING WATER ON THE BURNING BOXES."
This nitroglycerin-mill, it seems, was on the Pacific coast, whence they used to ship the dynamite on vessels that loaded right alongside the yards. One day a mixing-house exploded, and hurled burning timbers over a vessel lying near that had just received a fresh cargo. Her decks were piled with boxes of explosives—wooden boxes, which at once took fire. When this "certain man" rushed down to the dock, the situation was as bad as could be. There were tons of dynamite ready to explode, and a hot fire was eating deeper into the wood with every second. And all the workmen had run for their lives!