Why, nearly every time Cliff wanted to make a trip across the line, those kids climbed the hill to where they could look all over the flat and the near-by hills, and if they saw any one they would yell down to Mateo.

If the interloper happened to be close, they had orders to roll small rocks down for a warning, so Cliff one day told Johnny with that insufferably tolerant smile.

Cliff brought them candy and petted them, just for what use he could make of them as watchdogs.

Would all that be necessary for a legitimate enterprise?
Wouldn't the guards have orders to shut their eyes when an airplane flew high, bearing a man who gathered news vital to the government?
Once before Johnny had been made a fool of by horse thieves who plied their trade across the line.

They had given him this very same airplane to keep him occupied and tempt him away from his duty while they stole Rolling R horses at their leisure.