He knew they were Indian ponies by their size, their variegated colors, and their general unkemptness.

They presently spied him and went galloping off up the gulch, and Casey followed until he spied a thin bluish ribbon of smoke wavering up toward the slate-black clouds.
He made camp just out of sight around a point of rocks from the smoke, stretching the canvas tarp which had floored the tent to make shelter between boulders.

He changed his clothes, dressing himself carefully in the white flannel trousers, blue-and-green striped silk shirt, tan belt, white shoes and his old Stetson tilted over his right eye at the characteristic Casey angle.

He was taking it for granted that an Indian camp lay under that smoke, and he knew Indians.

Inquisitiveness would shut them up as effectively as poking a stick at a clam; but there were ways of coaxing their interest, nevertheless, and when an Indian is curious you have the trumps in your own hand and it will be your own fault if you lose.
Casey's manner therefore was extremely preoccupied when he led a suddenly limping William up the gulch and past a stone hut with a patched tepee alongside it.