This showed the course by the compass, and was expressed in degrees, minutes and seconds.  The poor reading of a course is one of the frequent faults of new or careless engineers.

“Here is a magnifier for the vernier,” continued Rutter, just after Tom had started to make his reading.

“Thank you; I have a pretty good one of my own,” Tom answered, diving into one of his pockets and bringing to light a small but powerful reading glass with an aplanatic lens.

“You carry a better magnifier than I do,” laughed Rutter.  “Hazelton, do You carry a pocket glass?”

“Yes, sir,” nodded Harry “I have one just like Reade’s.”

“Good!  I can see that you youngsters believe in good tools.”

Tom in the meantime was busy with the vernier of his transit.  This is an ingenious device for showing the smaller divisions into which the circles of the compass are divided.  Tom quickly jotted down his field note in degrees, minutes and seconds.  One chainman now held an end of a hundred-link chain at the nail head on the stake, while a second man started toward the rodman, unfolding the chain as he went.

Tom remained over his transit.  The traveling chainman frequently glanced back for directions from Reade whether or not he was off the course of a straight line to the next stake.

Soon the chain-bearer was a little to the left of the line.

Tom held a hand over the telescope of the transit, moving it very slowly to the right.  The chain-bearer, glancing slowly back, stepped slowly to the right of the course until Tom’s hand fell abruptly.  Then the chain-bearer stopped, knowing that he was on the right line.  A metal stake, having a loop at the top from which fluttered a marker of red flannel, the man stuck upright in the ground.  Tom took a peep, signaling so gently that the man moved the stake just half an inch before Reade’s hand again fell.

“That stake is right; go ahead,” ordered Tom, but he said it not by word of mouth, but merely with a slight gesture of pushing forward.

“You’ve been well trained, I’ll bet a hat,” smiled Butter.  “I can tell that by the practiced way that you signal.  O’Brien!”

“Yes, sir,” answered another chainman, stepping forward.

“Take Thane with you, and carry Mr. Hazelton’s transit to Grizzly Ledge.  Mr. Hazelton and I will be there presently.”

Two more chainmen started away.

Now, both of Tom’s chainmen started forward, the rear one moving to the first metal stake that displayed the red marker.  Tom still remained at the transit, motioning to the men whenever they got the least out of a true straight line to the rodman.  It was not hard work for Reade at this point, but it required his closest attention.