3 DECEMBER 1954, Page 15

Chemical Wonders The young farmer spoke of the price of

feeding hens and remarked that he had 500 birds on deep litter, a method he considered superior to others. His one trouble, he informed me, JAW been when the rat popula- tion suddenly increased from one or two to several hundreds. It was not a question of rapid breeding. The rats had been attracted from other places. They began to equal the birds in number, and since there was so much food about, the question of getting rid of them was not exactly a simple Dile. Traps were out of the question and a bait more attractive than the food was needed— something that the birds would not take, or if they did, would do them no harm. The bait was found. It was a proprietary thing that proved an almost Pied Piper magic, for the rats were eliminated almost as quickly as

they had appeared, The substance proved harmless to all other creatures but rats and mice. The rats withered away. A wonderful

thing,' said the young farmer. I wouldn't like to have a research chemist among my enemies, I can tell you ! ' I have often thought the same thing. The atomic explosion devastates square miles but there arc more fiendish things that can be kept in bell-jars, mixed in test-tubes or cultivated on cotton wool.