The mystery explained
On one occasion, whilst examining the machinery of the monster revolving lamp belonging to a lighthouse, a visitor, wishing to see how many seconds would elapse before it completed a revolution, took a half-crown from his pocket, and placed it on the revolving framework.
Watch in hand, he patiently waited for the coin to come round again to where he was standing, but no half-crown appeared. The seconds lengthened out into minutes—still no half-crown.
“Strange!” he exclaimed. “What can be the reason of it?”
In order to find out, he walked to the other side of the lamp, and met one of the lighthouse men, who touched his cap and said respectfully,
“Thank you, sir.”
[from the Rockhampton newspaper The Capricornian, 14 December 1907.]