This is a game of leapfrog.
I. Two players make a back. They stand with backs to the jumpers and place their inside hands on each other’s shoulders with arms extended at full length to leave a space between. The jumper places a hand on each of the inside shoulders. The push will be away from the center and the backs will need to brace themselves for this.
II. A back is made by two or more players standing close together with sides toward the jumpers, thus making a back several widths deep to jump over.
For whichever form of back is used, any player failing to clear the back without touching it is out of the game, the first two failing becoming backs for the next round when all have jumped. For large numbers of players this may be played as a competition between different groups.
Games for the Playground, Home, School and Gymnasium by Jessie Hubbell Bancroft