Generally speaking he needed but one hint to do that.

His commander climbed out, or fell out, from beneath the boot.

The ground upon which he fell was damp but firm.
"Whoa!" he roared again.

Then scrambling to his feet he sprang toward the wagon, which, the forward wheel detached and flat beneath it, was resting on the remaining three in a fashion which promised total capsizing at any moment.
"Be you hurt?
Be you hurt ?" demanded Winnie S.
From inside, the tightly drawn curtains there came a variety of sounds, screams, exclamations, and grunts as of someone gasping for breath.
"Be you hurt ?" yelled the frantic Mr.Holt.
It was the voice of the younger passenger which first made coherent reply.
"No," it panted.

"No, I--I think I'm not hurt.