“In his office.”

He found Mr. Taylor busy over some blue prints. The engineer looked up as he entered and Bob at once saw that the man was angry. His first question proved it.

“What the dickens do you mean by not reporting this morning? Just because Mr. Whitney is away, do you think you can take a vacation when you feel like it? And King, too; wait till I get hold of him! But what have you got to say for yourself, young man?”

“I couldn’t help it—”

“Couldn’t help it!” exploded the irate man. The total responsibility for the project had fallen on him for the past few days and it had made him nervous. “Of course you could help it. You’ve got to help it if you belong to the Service!”

Bob waited until the storm had passed and then asked calmly:

“Has the Chief told you he suspects trouble with the Mexicans?”

The man looked at the boy sharply but made no reply. From his manner Bob was sure that Mr. Taylor knew but did not wish to confess his knowledge. Figuring that his silence was equal to an assent, Bob went on:

“Mr. Whitney told me something about it and the reason I’m late to-day is that I got mixed up in the mess—”

This startled Mr. Taylor.