The Ring of Truth

PC Bloggs has an amusing piece about the customary scramble among police officers to get their hands on a new bit of kit.
I am on drinking terms with an old-school retired Met. Sergeant, and he told me many years ago about the Met's propensity to destroy expensive equipment. When London's finest received their first proper helicopters (great big Bell 222s) one of them was soon involved in an 'incident', to the surprise of no-one. My pal told me a canteen story about an academic who was making a study of psychology, and conducted an experiment in which he gave two large steel spheres to a teacher, an artist, and a Metropolitan Policeman, with instructions to put them to good use and report back in a week.
The teacher reported that he had used his spheres to teach basic physics, encouraging his pupils to roll the spheres on a flat surface and to record what happened when they struck each other. "Excellent" said the professor. The artist had lined a large bowl with paper and dipped the spheres in inks of different colours before rolling them around. The paper was then flattened out to reveal fascinating patterns of colour. "First rate" said the prof. He turned expectantly to the policeman. "Well, I lost one of them, and the other one's broke" was the reply.