This was true. The substance before them was different in its appearance from gunpowder in two respects. It was not grained like gunpowder, but was fine and impalpable, like dust. Then it was of a lighter color. Mixing so much saltpetre, which was white, with the charcoal and sulphur, prevented its being so dark as common gunpowder. At least, Mr. Holiday thought that this was the reason, and he suspected that, in some way or other, he had got too much of the saltpetre in his composition. At any rate, the powder looked like nothing but a heap of gray dust.
“The proof of the pudding is the taste,” said he; “so we’ll try it.”
He accordingly took up about half a tea-spoonful of the gunpowder, and put it upon the shovel, and he asked Jonas to hold it in the fireplace, so that, if it did burn, the smoke might go up chimney. Rollo wanted to touch it, and his father gave him leave. So he took up a small coal of fire with the tongs, and touched the top of the little heap. To their great pleasure and surprise, it blazed up suddenly and violently.
“Yes,” said Rollo, “it’s gunpowder! It’s real gunpowder, I do believe!”
“Let me touch some of it,” said James.
Mr. Holiday put another half tea-spoonful upon the shovel and let James touch it. It flamed up like real gunpowder, just as before.
“The great peculiarity of gunpowder,” said Mr. Holiday, “is, that it burns without air. Other combustibles, when shut up in a confined space, will not burn. If they are set on fire previously, they go out when they are closely shut up from the air. But gunpowder burns the more violently the more closely it is shut up. There seems to be something in some of the ingredients which takes the place of air; so that, when people drill a hole in a solid rock, and pour gunpowder down to the very bottom of it, in a place where nothing else would burn, and then ram down pounded bricks into the top of the hole, so that no air can get in, if they get fire to the gunpowder, it will burn there more fiercely than any where, and tear the rock to pieces.”
“How do they get the fire down?” asked Rollo.
“They put a wire in,” replied his father, “before they put in the bricks; and then when the bricks are pounded in hard, they draw up the wire, and that leaves a little hole extending down to the powder. Then they pour fresh powder into the hole, and put shavings on the top, and then set the shavings on fire, and run away.”
“I should like to see them blow up a rock,” said Rollo.