Rutter's pony reared.
"Still, you brute!" commanded Rutter sternly.

Then, without waiting to see whether his mount would stand alone, Rutter leaped from saddle, going forward with his quirt---a rawhide riding whip---uplifted.
Into the brush from which Tom had stepped Rutter went cautiously, though he did not lose much time about it.
Swish! swish! swish! sounded the quirt, as Rutter laid it on the ground ahead of him.

Then he stepped out.

The pony had drawn back thirty or forty feet and now stood trembling, nostrils distended.
"Is that the way you take your exercise ?" Reade demanded.
Rutter, however, came running along the trail, his face white as though from worry.
"Reade," he demanded, "Did that thing strike you ?" "What thing," asked Tom in wonderment.
"The rattler that I killed!" "Rattler ?" gasped both cub engineers.
"Yes.

From the distance I thought I saw it strike out at you.
There's a nest of the reptiles at some point near that brush.
That's why I warned you to get away from there.