“Why, it ought to be six times as much saltpetre by weight, and not by measure. It wouldn’t take six tea-spoonfuls of saltpetre to weigh six times as much as one tea-spoonful of sulphur, I presume; for I should think saltpetre is much heavier. I suppose saltpetre is heavier than either sulphur or charcoal. So I will put in two tea-spoonfuls of sulphur, and two of charcoal, to make up for their lightness.”
“I should think it would be better to weigh them,” said Rollo.
“Yes, it would be rather better, but it would take more time, and we will see how our gunpowder burns without being exact in the proportions; and if it does not succeed, then perhaps I will try again, and weigh out the ingredients, and see if it makes the gunpowder any better.”
While saying this, Mr. Holiday had been gently rubbing and mixing the powders in the mortar. He said he must rub them gently, for, as the pestle and mortar were both of iron, if he rubbed hard, he might possibly set his gunpowder on fire.
“O father,” said Rollo, “I don’t believe it would take fire by just rubbing in a mortar.”
“No,” said his father, “I don’t think it would, myself; but it might, possibly. I have heard of powder-mills taking fire by the friction of the mills in grinding the powder,—though I don’t suppose it would be possible to set fire to any such powder as we can make, by rubbing it in a mortar. Still it is well to be on the safe side.”
After Mr. Holiday had mixed the compound sufficiently, he poured it out of the mortar upon the sheet of brown paper which Jonas had prepared.
“Is that gunpowder?” said Rollo, in a tone of incredulity.
“I think it is somewhat doubtful myself,” replied his father.
“It does not look like gunpowder,” said Rollo’s mother.