Carley had reached a limit of strength, endurance, and patience.

She hauled him up short.

When Spillbeans evinced a stubborn intention to go on Carley gave him a kick.

Then it happened.
She felt the reins jerked out of her hands and the saddle propel her upward.

When she descended it was to meet that before-experienced jolt.
"Look!" cried Flo.