JACK'S "BIT OF ENGINEERING."
The boys got around Jack after dinner, and asked him about that bit of engineering.
"In the first place," said Jack, standing outside the door, and looking over toward the spring, hidden by intervening bushes on a ridge, "we must have a water-level, and I think I can make one. Get me a piece of shingle, or any thin strip of wood. And I shall want a pail of water."
A shingle brought, Jack cut it so that it would float freely in the pail; and, having taken two thin strips of equal length from the sides, he set them up near each end, like the masts of a boy's boat.
"Now, this is our level," he said; "and these masts are the sights. To see that they are exact, we will look across them at some object, then turn the level end for end, and look across them again; if the range is the same both ways, then our sights are right, are they not? But I see we must lay a couple of sticks across the pail, to hold our level still while we are using it."
The boys were much interested; and Link said he didn't see what anybody wanted of a better level than that.
