Science Siftings

New Zealand Tablet, 24 August 1916, Page 43

Science Siftings

By ‘Volt.’

Life of a Battleship. Naval experts put the active life of a modern battleship at about fifteen years. A hundred years ago battleships lasted nearly six times as long, and were on active service nearly the whole time of their commission. The Victory, for instance, was forty years old when she acted as Nelson’s flagship at the memorable Battle of Trafalgar. A iine-of-battleship, the Royal William, was built at Chatham in 1670, and was not broken up until 1813, being ‘ rebuilt ’ several times before her demise. Pace Lengths. How many steps do you take to the mile ? Even if your considered reply be * 1760/ I shall take leave to doubt it. Should you be a British infantryman your pace will be the longest of any infantryman in. the world. The Russians pace is the shortest, being butinches, the French, Italian, and Austrian pace is--29 inches, the German do. 31 inches j whilst we stride an extra half an inch. But your own pace, what of it ? It depends upon your height. Take your eyebrow height, halve it, and that represents your pace. You will find it to be somewhere between 30 and 32 inches, so that you will need between 2000 and 2100 paces to the mile. The Sleep of Fishes. It has often been asserted that fish never sleep, asufficiently amazing theory that anything can do. violence to the great law of nature. Brehm, on the contrary, used to contend that fish slept soundly, assuming during that time certain peculiar attitudeswhich could not be construed otherwise than as attitudes of sleep. The experiments of M. Reinhardt, asdetailed in the Science au Vingtieme Siecle, go far to confirm Brehm’s theory. He paid particular attention to the loach, which, he found, assumed an attitude of repose, during which its functions were less active, and the keenness of its sensorial faculties was, diminished. It sleeps at any hour of the day or night,, and in doing so it rests on its caudal fins, the body being slightly bent, while the head sometimes leans up against the sides of the aquarium or an aquatic plant.. Respiration is weak at these times. ■ Sometimes it slips', round on its back, and remains in this position absolutely motionless for hours, its sleep being anything butlight. Other observers agree in saying that fish, sleep. Wonderful Plants. There are many strange species in the vegetable world, and among some of the queerest may be mentioned what is called the telegraph plant. This plant, hails from India, and each of its large leaves is composed of three portions. During the day the largest, one stretches out towards the sun, so as to catch the full warmth and brightness, but when night comes on the big leaf turns down, while each of the small petals works day and night, moving, as it were, independently. They describe, in somewhat jerky movements, .complete circles, thus deriving their name. Then there is the strange fishing plant, under the sea, which opens and shuts periodically, like a big mouth. When fishes are near enough to this wonderful plant, all of a sudden it closes its ‘ mouth ’ and swallows them. In that wonderful land. South America, there is a terrible bush or plant which is like an octopus. An explorer not so very long ago was in the district whele this plant grows. Suddenly he heard a howl of pain and terror from his dog. He rushed to the rescue and saw that the animal was firmly caught in the rope-like-meshes and tentacles of a big . plant, which, were wrapped round its body. He had to cut the dog free, and when his hands came in contact with the fibrous meshes they became very blistered and red.