Then he signaled back with his right hand.

Tom Reade, in the meantime, had quickly set up his transit over the first stake on his part of the course.

He did some rough shifting, at first, until the point of the plummet was exactly over the nail head.

Then followed some careful adjusting of the instrument on its supports until two fine spirit levels showed that the compass of the instrument was exactly level.
"Now, let me see you get your sight," urged Rutter.
Tom did so, coolly, manipulating his instrument as rapidly as he could with safety, yet not with speed enough to cause himself confusion or worry.
"I've got a sight on the rod," announced Reade, without emotion.
"Are the cross-hairs, as you see them through the telescope, just on the mark ?" Rutter demanded.
"Yes, sir." "Let me have a look," ordered Rutter.

"A fine, close sight," he assented, after taking a careful look through the telescope.
"Now, take your reading." This showed the course by the compass, and was expressed in degrees, minutes and seconds.