Two cows were chatting over the fence between their fields. The first cow said, "I tell you, this mad-cow-disease is really pretty scary. They say it is spreading fast; I heard it hit some cows down on the Johnson Farm."
The other cow replied, "Ah, I ain't worried, it won't affect us ducks."
ColorscopeIn 1930, the Colorscope was first publically demonstrated in New York City. It used a photocell that reacts to colours of light, and could match colours more exactly than the human eye. The tiny electrical current generated was sufficient to operate relays or meters. It was invented by Harold H. Sheldon and Dr. Walter A Schneider. |
