Young's Improved Fly-Guard detector lock.

Patented July 1831 Thomas Hickin- Sole manufacturer To prove to the public the value and importance of this invention, the patentee connected an example of his lock to Mr. S. Underhill's steam engine, at Wolverhampton, where it was worked for thirty-three days, being locked and unlocked twenty-eight times per minute making a total of upwards of six hundred thousand times. When taken from the engine it worked as perfect as when it was new. So confident was the patentee that he wagered £20 "to any man that can pick the lock, and up to £100 to any lockmaker that can produce a lock more secure than this". It is not recorded if his challenge was accepted.