Suddenly a tremendous jerk at his mouth is accompanied by a most disagreeable sensation in his stomach.

He tries to pull away from both the entanglement and the sensation, but finds himself caught and held fast.
Mark gives a cheer as he jumps up from his uncomfortable position at the bottom of the ferry-boat, and Frank echoes it as he dashes out of the bushes and seizes hold of the line.
Now the alligator pulls and the boys pull, and if the line had not been made fast to the post, the former would certainly have pulled away from them or dragged them into the river.

He lashes the water into foam, and bellows with rage, while they yell with delight and excitement.

The stout post is shaken, and the Manila line hums like a harp-string.
"It'll hold him!" screams Frank.

"He can't get away now.