SCIENCE SIFTINGS

New Zealand Tablet, 22 May 1919, Page 46

SCIENCE SIFTINGS

By "Volt."

Caterpillars; Stop Trains. . v , No story of a trip on the early transcontinental railroad was considered complete without an account' of delay due, to herds of buffalo and flocks of grass-' hoppers crossing the track. The buffalo has disappeared, and grasshoppers no • longer give trouble; but there is still one of Nature's creatures whose desire for a life on the rail occasionally causes trouble. The McCloud River railroad runs from Sisson to McGavie, California, through a territory where caterpillars exist in large numbers. During the spring these insects climb on the head of the rail and cover it completely. As the caterpillars are crushed under the wheels, both the wheels and the rails become so slippery that it is impossible to haul a train or to stop it effectively with the brakes. On heavy slopes the locomotives slip and the trains start to slide backward down the hill. Trenches dug along the right of way are often effective in stopping the progress of the pests, but the distance over which they advanced made such a procedure impracticable in this case. Brooms and scrapers on the locomotives proved worse than useless, for they crushed the caterpillars instead of removing them. The solution of the difficulty was found in steam jets directed at the rail a short distance ahead of the wheels of the locomotive. By this method the caterpillars were blown 20 or 30 feet from the rails and about half of them were killed. Gas Attacks and Sparrows, Investigations of the effects of poison gas on animals show that horses suffer considerably from the noxious fumes and are subsequently thrown into a state of nervous terror on again scenting them. Mules are inclined to stand their ground, and appear as if trying not to breathe. Gas helmets of a kind have been successfully tried for both these animals. In the trenches many animals are kept by the soldiers as pets. Of these, cats quickly detect gas and run about howling. Guinea-pigs are the first to succumb. Mice, emerge from their holes and are found dead in quantities. Poultry of all kinds are useful for giving warning clucks and fowl becoming agitated 10 minutes or so before the oncoming gas clouds. Many kinds of wild birds are greatly, excited, and the usually unruffled owl becomes, as it were, half-demented. Only the sparrow seems to disregard the poisonous vapour, and sparrows chirp on where horses are asphyxiated, and bees, butterflies, caterpillars, ants, and beetles die off in great numbers,. . . The gas at once kills snakes, and earthworms are found dead in their holes many inches below the ground. " ""' 553