Cat's eyes are small devices designed to mimic the reflective properties of cat's eyes. In Britain they are set into some roads so that drivers can use the spots of reflected light to find their way along roads in the dark.
Cat's eyes were invented by a Yorkshire roadworker called Percy Shaw.
The story goes that one day Percy was driving home in the dark down a deserted road when he saw two spots of light in midair in front of him. These small circles of light were in fact his car headlights reflecting off the eyes of a cat which was sitting on the fence by the side of the road. If the cat hadn't been there Percy would not have realised that the road turned a corner at that point and would doubtless have driven straight on through the fence and to his death at the bottom of the steep hill beyond it.
This near death experience shook him up so much that he spent the next year trying to invent something like the eyes of a cat which could guide drivers in the dark.The resulting "cat's eyes" consisted of two prisms
and an Aluminium mirror
behind them to reflect some of the light form car headlights back into the eyes of the driver
Unfortunatly his inventions soon became dirty in the middle of roads so he modified the design so that when cars drove over the rubber casing of a cat's eye the prisms inside were pushed past a rubber pad which wiped them clean.
On April the 3rd 1934 Percy laid his first fifty cat's eyes on a stretch of road near Bradford which was renouned for accidents. The number of crashes dropped dramatically and the ministry of transport approved Shaw's idea and began to install cat's eyes across the country.
Percy Shaw's invention made him a millionaire and in 1965 the Queen awarded him the OBE.
Today cat's eyes are used all over England and have probably saved thousands of lives. They are now also colour coded as follows.
WHITE Separates lanes of traffic going in opposite directions.
AMBER Marks the offside of motorways.
RED Marks the nearside of motorways.
GREEN Marks public sliproads.
BLUE Marks police only sliproads.