Tom busied himself in picking out the best leveling instrument in camp, while Hazelton secured the rods and a chain.

Then the party set forth in Indian file, Tom riding in advance.
A trot of half an hour brought them to Section Nineteen.

Here Tom speedily adjusted his instrument, taking up his post over the first stake at the bottom of the hill.
Leveling is not difficult work, though it calls for some judgment and a good deal of care.

For instance, when Tom set his telescope exactly level and took a reading of the rod at the second stake, which Harry held, he read the height as eight feet and four inches.
Then he trudged forward, carrying his instrument, while Trotter held his rod exactly perpendicular over the first stake.

From the second stake Tom sighted back through his telescope, reading two feet three inches.