SCIENCE SIFTINGS.

Auckland Star, Volume XXXVIII, Issue 136, 8 June 1907, Page 10

SCIENCE SIFTINGS.

EFFECT OF X-RAYS ON THE HAIR. Increasing ejjperience confirms the observation that X-rays have a remarkable inflnence upon the colour of the hairProf. A. Inibert and M. H. Marques, two French experimenters, find the influence to be real and enduring, but they are unable to explain it. The white hair and beard of one of these authorities, who has been engaged in X-ray work since 1896, have not only been restored to their original colour but are even darker than before. In an elderly patient, under treatment for lupus, part of the hair fell out under the action of the rays, but it soon grew again, and it has been since almost completely black. TEETH WORSHIP. Teeth have been worshipped, and, in fact, are venerated as relics in some religious shrines. Buddha's tooth is preserved in an Indian temple. The Cingalese worship the tooth of a monkey. , while an elephant's and a shark's tooth • serve a similar purpose among the Malabar islanders and the Tonga islanders respectively. The Siamese were formerly the possessors of the tooth of a sacred monkey. which they valued very highly. In a war with the Portuguese they lost the holy grinder, along with much gold and precious stones. PURSUED BY A SPIDER. A story is told by an explorer of a large and fierce South American spider which chases men if they come too near its lurking places. On one occasion he was pursued by one. '"Riding at an easy trot over the dry grass," he writes, _ observed a spider pursuing mc. leaping swiftly along arid keeping up with my beast. I aimed a blow with my whip, and the point "ol 1 the lash struck the ground close to it. : when it instantly leaped upon and ran up the lash, and was actually within threw or four inches of my hand when I flung the whip from mc." GROWTH OF THE FINGER NAILSThe growth of the average finger nail is computed to be one-thirty-second of an inch a weak, or a little more than an inch and a-half a year. Imagine the care taken by the aristocratic Chinese in cultivating their finger nails, which often grow to be six or eight inches long- Just think of letting your finger nails grow fdr eight years without cutting them!-

The finger nails are said to grow faster in the summer than in the winter. The nail on the middle finger grows faster than any of the other naiks, and that on the thumb grows slowest. It is also said that the nails on the right hand grow faster than those on the left hand.

According to the rate of grow*ft stated, the average time taken for each* finger nail to grow its full length is about four and a-half months, and at this rate a man seventy years old would have renewed his nails one hundred and eightysix times. Taking the length of each nail as half an inch, he would have grow;n seven feet nine inches of nail on each finger, and on all his finger? _.<i thumbs a:.i aggregate htngth of fji-.teet. GERMAN L.EV7ATHAN. At present the White Star liner Adriatic, which has yet to make her maiden voyage, holds the record =for the largest Atjlantie vesseL _it Germany, "Is determined to .-.snatch" the record. An order was recently placed by the Hamburg-America Company with Messrs, Harland and WcDI for a vessel of 2">.700 tons. The gross tonnage of the Adriatic is 25.000. In every other respect, it is understood, the dimensions of the new German ship will exceed those of the White Star liner, which are: — Length over all, 725 ft 9in. Breadth, 75ft 6in. Depth, 50l"t. Accommodation for 3000 passengers. It is proposed to equip the new German boat ou the same palatial lines as the White Star liner, which has, amongst other luxuries, an electric lift, Turkish hath, a photographer's dark room, and a gymnasium. SCIENTIFIC SPORT WITH KITTENS. At tbe recent annual meeting of the New York Academy of Sciences a. member, of the faculty of Columbia Univeftlty described his experiments in comparative psychology, in which kittens, dogs, chickens, and monkeys played a part. One object was to show in what manner and how rapidly animals learn tricks. A box was provided with a door tha. could be opened from the inside by means oi a latch, or by pulling a cord or turning a button. Kittens were placed inside the box and a toothsome fish • outside. The time taken to get out became gradually shorter, but the Columbia University man found that the trick was always learned by accident. One lucky hit would prepare the way for another. He could see no trace of rational inference on the animal's part. It was not possible to teach the trick by taking the kitten's paw and pushing the latch, and the; seeing another animal do the. trick a hundred times was no help to the one that had not already learned it-

CLEVER OPTICAL LLLI*SION*. Visitors at the Museum of Natural History in New York are sam to have an opportunity lo see something entirely novel in the way of pictures that ha.ye all the appearance of real life. As they pass along a e-orridor, they will look tli rough a series of windows, and will behold landscapes ajid birds of different kinds, the view extending seemingly over immense distances.

Of course, it is a trick of optics, _.ufc certainly most ingenious and admirable. In each instance the scenery is painted on t-anvas, and the pitrture, exquisitely executed, merges imperceptibly into a real foreground, after the manner of the panorama- Each scene occupies a sort of box not more than fifteen feet square by nine feet in height, the back made concave; but the effect is so artfully contrived that one is easily deceived into imagining that the prospect extends over many miles.

For example, one of the scenes represents Pelican Island, in the Indian River. Florida, a place frequented by thousands of breeding peli<a.ns.. which are there protected by the against ifTterferenee by self-styled sportsmen or other depredators,' Utmost pains have "«-_en taken to reproduce the aspect of tlie surroundings with a literal frankness, and ove< acres of territory the birds are seen on their nests or feeding their young. In the foreground are real stuffed and life-like pelicans, similarly engaged, with sand and clumps of veseta-tion to itelft out the ilhi_.n.

Another scene shows sandhill cranes in a swamp, their eggs in a nest that looks as if it floated on the water. Of course, the water is a mirror, and there arc real rushes, and water plants in the foreground, merging into the paaStted vegetation oi the middle distance.