Jumping-jack

In the beheaded frog the legs twitch as fatally when we touch the skin with acid as do a jumping-jack's when we pull the string.

"Because you are built as absurdly as a jumping-jack," sneered the horse, rolling his knotty eyes in a vicious manner. "Even your head won't stay straight, and you never can tell whether you are looking backwards or forwards!"

"I have a jumping-jack!" came from Freddie, and he began to work the toy up and down in a most comical fashion.