Science Siftings

New Zealand Tablet, Volume 19, Issue 42, 19 October 1905, Page 29

Science Siftings

By « Volt '

Roentgen Rays an«d Leprosy. In the leprosy experiments at Manila, 25 cases have been treated by Roentgen rays, and six are repv>rted-ac-tually eared, while the disease has been cheeked in several whose bodies are partially gone. Imitation Pearls. The most successful imitation pearls are htollow glass balls lined with silvery and iridescent fish-scales. The scales 1 come from a small fish known to the English atf the bleak, and must be picked off by hand, 18,000 fishes being required to supply a single pound of perfect scales. 'The artificial pearls are made in France. Minute Writing. The Declaration of Independence has been written, with the aid of glasses, on a scrap of paper no larger than a quarter of a dollar. Yet this is npthing to a feat for which Cicero vouches. He said that he had seen the entire ■' Uiad '—a poem as long asi the New Testament— written on skin so that it could be rolled up within the compass of a nutshell. Cure for Hay Fever, The hay fever serum, or poll'antine, of Dr. Dunbar of Hamburg is shown to have been very elective. Haiving first proved that hay fever is due to the pollen poison from grasses, cereals, and other plants, the investigator sowght a preventive by repeated vaccination of animals with the poison of pollen . The antitoxin thus produced serum, which neutralises the poisonous effect of pollen m Ihe eyes and nose. The serum is not injected under the skin, like others, but simply applied to nose and eyes. Sea-Snakes. While the existence of the monstrous sea serpent, of which marine travellers periodically tell marvellous stories, is pretty generally discredited, there is no question about there being such reptiles as sea-snakes. They are from two to four feet long, are absolutely aqmatic, and are found, in forty or fifty different kinds, from the Persian G-ulf to the Philippines, and also on the coast of Central America. One well known species is the ' herril,' found lin the Bay of Bengal. These serpents are extremely poisonous, and consequently very dangerous to fishermen, pearl-divers, and bathers. 1 iiutugiauhy luiutr Ualci. The mysterious 11 fp that goes on beneath the surface of a lake or ptiearij, or even ol the sea 1 1 self, may now be seen, and thrjt wiihout the necessity of diving into the depths which it is desired to explore. The wonder is accomplished by means of the cystoscope, a bient tiuibe (which may be attached to any camera. One end off this tube, containing an Edison illuminating contina f 1 is placed in the water, and a prism, designed to refect the images at the end of the cystoscope, and place in the bend of the tube, enables the photographer to ake photographs of scenes under water. The process is so simple that any amateur photographer can master it, and in the case of lakes or rivers, \w£k'h abound vith fish and aquatic plants, some re-ally exquisite pictur«s may be taken. Animal Becoming Extinct. E\ery century sees several species of animal becoming extm.t In the ace for life the weak must yield to the strong, and b cause they are persistently sought for food ox for feathe s, not only individuals, but whole families', cease to c ist. The disappearance of the great auk can be lail to the nineteenth century. It became extinct on c American side of the Atlantic about 1810, awd in E rope about 1814. The South African (fuagga disappear*! about 187-0, owing to the slaughter by hide hunters. The twin-shelled tortoise of the Galapagos Islands >ecame extinct in all nrobabilitv about 187:5. The bh.'k emu of South Australia was also exterminated di ring the century, though it was abundant in 1803. Tie great cormorant was last seen alive about 1839, and many other species of birds, from all parti of the wor'l, have likewise been exterminated . In the Danish West ndia Islands, for examjDle, out of fourteen species catasgiued in 17>95 only six still exist ; and a similar historj can be told of many other localities.