This section is from the book "The Boy Mechanic Vol. 2 1000 Things for Boys to Do", by Popular Mechanics Co.. Also available from Amazon: The Boy Mechanic, Vol2: 1000 Things for Boys to Do.
Some means must be provided on vaulting-pole standards to allow for the free release of the pole should the vaulter strike it in going over. One of the simplest of the many devices that can be used for this purpose is shown in Fig. 1. It is made of heavy wire, bent and slipped over the standard as shown in Fig. 2. The projection on the inside of the link is used similar to the tongue of a buckle in adjusting the height of the pole on the standards.
Each standard has a series of holes on its front side. These holes may be numbered for convenience. The pole in place is shown in Fig. 3. - Contributed by John Dunlap, Craghead, Toll-cross, England.
Ill: Pole Adjuster on Standard