SCIENCE NOTES.

Otago Witness, Issue 3005, 18 October 1911, Page 76

SCIENCE NOTES.

—Artificial Mountain Sunshine.— The scientist B-regier ascribes the benefit of sunlight at high altitudes to the preponderance of the ultra-violet rays, which induce an active superabundance or congestion of blood, lasting for hours, without any tendency to sweating. He believes that the same result can be obtained "with artificial light rich in ultra-violet rays, and is experimenting along this line. —Science for Its Own Sake.— Sir James Dewar recently pointed out that the whole cost of a century's research of experiments at the Royal Institution has been only about £I2OAX)O. What an insignifioant sum to pay for the benefits mankind has receivedl from the splendid investigations of Young, Davy, Faraday, Tyndall, Dewar himself, and others! Yet most of the labours of these men were carried out honoris causa, and not for immediate material benefit. —Power of an Air Brake. — Some idea of the power of an air brake may be gained from the following facts: It takes a powerful locomotive drawing a train of ten passenger cars a distance of about five miles fe> reach a • speed of 60 miles an hour on a straight and level track. The brakes will stop the same train from a speed of 60 miles an hour in 700 ft. Roughly, it may be stated that a train may be stopped by the brakes in about i> per cent, of the distance that must be covered to give it its speed.—'Science Conspectus. —•Safety Belt for Airmen.—

M. Esnault-Pelterie, one of the French airmen, has devised a safety belt designed to keep airmen from being thrown from their machines and to help break the shock of falling with the aeroplane. It consistsof a broad leather strap, which covers the whole of the chest and part of the abdomen, to the ends of which are attached powerful elastic straps, which- are in turn made fast to the machine by leather straps. Should the aeroplane meet with an accident, the shock is taken up by the elastic, and the airman is kept in his seat until parts of the framework or the wing structure" have broken the fall for him. —Subsitute for Platinum.—

It as been suggested that, in the preA r ailimg scarcity of platinum, the metal palladium might be a practicable substitute. It belongs to the platinum group, and has many of the qualities of platinum, although ia some respects it resembles silver. Among its valuable characteristics are hardiness, ductility, and malleability. It is also decidedly non-corrodible. It occurs, along with nickel, coppec, silver, gold, platinum, iridium, and rhodium, in the ores of the Canadian nickel mines in Ontario. Out of 300,000 tons of these ores about 3000 oz of palladium are annually produced.—Scientific American. —Submarines at Sea.—

Equilibrium is almost as difficult to maintain for a submarine vessel as for an aeroplane,. With modern large submarines the act 01 diving is performed! when the vessels have headway. The bow is depressed by horizontal rudders, and the vessel moves cbliquely downward. The desired depth having been attained, the steersman must so manage the horizontal rudders that the vessel shall practically maintain its level, but, in fact," its course becomes really an undulating one. There must be no movement of men or weight in the vessel without immediate compensation to restore and maintain the balance, else the submarine may dive to a disastrous depth;. Manual control has been found better than automatic oontrol —The Glow-worm. — The glow-worm is not a worm, but a species of beetle, to which the firefly or lightning bug is closely related. The true glow-worm is the female, and is ivithout wings. Its short legs and long body give it a vermiform appearance, and it can withdraw its triangular head into its neck. The adult insect feeds but little-; indeed, there is reason to suppose that the adult male does not feed at all. The larva, on the other hand, is carnivorous, and devours small molluscs, either dead or alive. The light given out by the glow-worm comes from a yellowish substance located on the underside of the abdomen. Though this light appears to (glow steadily, it is really intermittent., consisting of flaJshes in quick succession, about 100 to the minute. Besides the ordinary light rays, Bontgen rays are emitted. —Skin-colour.— Professor Lionel W. Lyde, at a recent B.M.A. Congress in Birmingham, dealt with the climatic control of skin-colour,

whorein he points out that they were in a position to say that primitive man was dark-skinned, and that when he began fco make his way northward he began to bleach, thus recreating a semi-primitive yellow type. This yellow man, exposed to conditions of cold and moisture, might become entirely white. The human skin develops pigments to protect itself against the strong sun, and' the quantity of pigments in the skin varied with the intensity of the sun. It is therefore in men who live in the hottest and least shaded parts of the world that we find the blackest skin. The white peoples, on the contrary, are confined to a .region where the humidity of the atmosphere forms a screen against the rays of the sun. —Queen Ants and Queen Bees. —

It is claimed that the queen ant has not had justice done her by naturalists. As compared with the famous queen bee, she is regarded by Dr W. M. Wheeler as a far more admirable creature. In fact, they are, in many important respects, diametrical opposites. The queon bee is, it is pointed out, a degenerate creature, unable to nourish either herself or bar young, to visit flowers, to build oombs, or to store them with honey. With the queen ant quite the reverse is true. She is held to be a perfect examplar and embodiment of her species, and the worker fcnt suffers from incomplete and retarded development. The queen ant is a very industrious and intelligent worker, and in the opinion of the authority mentioned, she forms an exceedingly interesting subject for study, and has not hitherto been well understood.

—Giant Seaweeds.— Climate affects the inhabitants of the sea just as it does those of the land. As Arctic land plants cannot flourish at the equator, eo in the Arctic and Antarctic oceans marine plants are found that are unable to survive in warm water. Among the most remarkable of these cold : water plants are the laminariacese, a Kind of seaweed, which sometimes attain a gigantio size, exceeding in length the longest climbing plants of the tropical forests, and developing huge stems like the trunks of trees. Investigation has shown that these plants flourish in the coldest waters of the Polar seas, and that they never advance further from their frigid homes than to the limits of "summer temperature" in the ocean. The genial warmth destroys them, just &S a polar blast shrivels the flowers of a tropical garden. ( - : •'•

—The Lure of Invention.— <

The lure of invention is one that influences all people and spares no class or condition of men. From the clergyman .'La his studly to the convict in his lonely cell (says the Scientific American) it exerts its attraction, and both are found enrolled among the list of patentees, although not so precisely identified. The stimulus is not always the hope of fee or reward, for we find the millionaire as strongly interested as the very poor. There is something in the attraction that cannot be Someone has said that writing is like flirting. If you cannot do it, no one can teach you to do it, and if you can do it, no one can keep you from doing it. So it is with invention: no one can teach you to do it, . and if you 'have the divine afflatus, no one can prevent you from exercising it. This is fortunate, for the inventor is subjected many times to discouraging influences in iihe first instance. Have you ever noticed, however, the pride with which anyone will display an invention even of the simplest character? Surely this is commendable, for we all admire originality, and invention is originality, often of the highest order. Whilfa the lure may be regarded apart from the results, we cannot help, realising ,what a poor world this would be except for the beneficent works of the inventors of all times. —The Origin of Man. —. Since Darwin first suggested the theory of evolution, scientists galore have been studying along the same lines, and man's origin is being gradually pushed further and further into the remote ages. Reviewing the "remarkable discoveries of the last 10 years in Western Europe, Professor M'Ourdly shows that it is being gradually that the human race is as old as any of the tailless apes, and probably had the same ancestors. The oldest undisputed flint implements date from the Upper Miocene period of geology, the oldest human bone, the jaw of Homo heidelbergensis, from near the beginning of the Quaternary. Primitive man, therefore, must have lived in Western Europe during the entire Glacial period, and developed into Homo primigeniue, low in stature and robust, with short, stout arms and legs—much like the Eskimo of to-day. A more intellectual race, probably from the East, appeared in the JJpper Quarternary, or at least 30,000 years ago. This people, Homo aurignacensis, sculptured and frescoed the walls of the caverns and their own implements, and their descendants, who must have flourished more than 10,000 years ago. introduced the rudiments of writing. The negroid people probably came into" Western Europe soon after Homo aurignacensis. Professor Klaatseh finds Homo primigenius to be closely related to the gorilla of Africa, and Homo aurr'fcrnacensis to resemble more nearlv the chimpanzee, of Asia.