Fas**ating photographs of London Zoo visitors horseback riding elephants and camels taken in the 1920s and '30s bear emerged.

The burnt sienna images hearken cover to the 20th **tury, yearn **nt carnal rights and health and rubber rules were discovered.

Photos shew lions, pivotal bears, chimpanzees and penguins in bleak, **crete enclosures rear prison-like metal bars.

Unmatchable startling mental image shows visitors standing on a little bal**y overhanging the pivotal deport penitentiary.