“All ready, sir,” he announced.

Mr. Thurston stepped over with an engineer’s field note book.

“See if these notes are all clear,” directed the chief engineer.

“Yes, sir; I know what the notes call for,” Tom answered confidently.

“Then I’ll show you just what’s wanted Reade,” continued the chief.

After some minutes of explanation Tom picked up the T-square, placing the top at the side of the drawing surface. Then against the limb of the “T” Tom laid the base of a right-angled triangle. Along this edge he drew his perpendicular north-and-south line in the upper left-hand corner. He crossed this with a shorter line at right angles, establishing his east-and-west line. Mr. Thurston, standing at the cub engineer is back, looked on closely.

Tom now settled on his beginning point, and made the dot with his pencil. From that point he worked rapidly, making all his measurements and dotting his points. Then he began to draw in. The chief engineer went back to his table.

After Tom had worked an hour the chief interrupted him.

“Now, Reade, get up and let me sit down there for a little while. I want to go over your work.”

For some minutes Mr. Thurston checked off the lad’s work.