SCIENCE SIFTINGS.

Auckland Star, Volume XLI, Issue 16, 16 July 1910, Page 14

SCIENCE SIFTINGS.

'A TEAR'S niVJSNTIOKrS. The story pf many inventions is told in. the annual report of Sir Temple Franks, the of Patents, Designs and Trade Masks. One ■of the outstanding features of 1909 was •the enormous development in aeronautics, the number of applications relating to this subject being more than three times the number received during the preceding year. Many of the inventions aim at perfecting the balance and control of aeroplanes. The prevalence of accidents, due to the unguarded points of ladies' hat-pins, as no doubt responsible for the great number of attempts that have been, made to devise a suitable point-<protec<tor. The number of inventions for improvements in roller skates has risen to a point even higher than was reached in the boom of 1875-6. ,VENOM V. VENOM. The remarkable combats of the Indian mongoose with venomous snakes, in which it always comes off victor, are well known. It has been suggested that it is immune to snake poieon. Other animals said to be immune are the pig and the hedgehog. With regard to the Kiongooss, ij) cN-j<?<J, this immiiiiifcv liiis been denied, and, if l>itten, it is said to fall a victim as rapidly as other animals. If this be true, then it niust owe its victories to ite wonderful agility in avoiding the bites of the reptile. However tills may be, somo recent experiments of Mons. G. Billard show that an animal of the dormouse family must be added to tho list of the immune. Thie animal is known as the X<erot, and is said to fight fiercely with vipers. M. Billard injected large doses of viper's poison into the lerot, and found that no ill-effects followed. On one occasion, again, one of them was bitten badly on the eyo by a viper, and no signs of poisoning followed. MAN'S STRENGTH. Inasmuch as a man's muscles develop with use, it would appear logical that the older he gets the stronger he should become, but such is not the case. Experiments made with thousands of men show that the muecles of the average man have their period of increase and decline, whether he uses them much or little. The average youth of seventeen has a lifting power of 2Solbs. By his twentieth year his power has increased to such a degree that lie should be able to exert a lifting power of 320105., while his maximum power is reached in his thirtieth or thirty-first year, 3Gslbs. then being recorded. At the expinution of the thirty-first year his power begins to decline, very gradually at first, falling but Slbs. by the time he is forty. From forty to fifty the decrease of power is somewhat more rapid, having dropped to 3301b5. at the latter age, the average lifting , power of a man of fifty, ■therefore, being slightly greater than | that of a man of twenty. After fifty the decrease in etrengtn is usually rapid, but tho rate of decrease varies so surprisingly in individuals that it has been impossible to obtain accurate <la.ta as to average strength after that age.

tMAQHIN~E THAT CRAWLS OVE& HILLS AND DITCHES. A monster engine with thirty-two feet, capable of drawing eighteen or twenty tons behind it, and able to reel and struggle at walking pace over dikes sft wide and np precipitous hills with gradients of one foot in two, may be seen over the Long Valley at Aldershot (writes a mail correspondent). Instead of running on wheels, this strange machine—a new "tractor" of the type designed by Messrs. E, Hornsby and 60ns, of Grantham, for hauling guns in war time over rough ground—-moves along on two huge, endless chaine, which pass over cog-wheels at each end of the apparatus. On the outside of these chains are the feet-blunt blocks of wood-metal-bound. Where wheels would slip into ditches and refuse to m-crve the many feet of this machine, which it plants down one before the other with a curious suggestion of cautious intelligence, enable it to roll on resistlessly. Hitching a field gun weighing ehc tons to the tail of the machine, a number of military experts directed its drivers to make it walk across a ditch nearly five feet wide. The front feet in doing so left one bank and seemed to feel their way across to the other side. Then, with a mighty lurch, and a groan, it swayed across. Quite dexterously the tractor "walked" down a steep bank into a roadway. Ifc moved with eaee also over soft, marehy soil. On level ground it ran along at a speed of twelve miles an honr.

SEA'S WEALTH OF RADIUM. A number of strange conclusions which may be inferred from the way the element radium is distributed over land and sea are discussed in "Radio-Chemistry" (Messrs. Dent and Sons), by Mr. A. T. Cameron, lecturer m Physiological Chemistry, University of Manitoba.

Of all the romantic treasures in the sea surely radium is the most wonderful. It has been computed that in the combined ocean waters there are 20,000 tons of radium. As the market price of radium is £ 15,G50,000,000 per ton it is clear that an almost fa-bulous fortune awaits the fortunate individual who can devise a means of extracting this treasure.

In this fact of the distribution of radium ovtrr the earth, for there is always more radium in a land surface than in an equal extent of ocean surface, lies very possibly the explanation of many of the most familiar freaks of the weather. Eain, snow, etc., a-re inevitably connected with, the radio-activity of the atmosphere as the ions—electrically charged particles—which it causes act as centres for condensation when the amount of water vapour is sufficiently great.

Another strange effect of the wide distribution of radium is the earth's heat, and from the rate at which radio-active ■minerals disintegrate the earth's age can be computed. One calculation put the age of the mineral thorianite at about 700 million years.

The future of the earth, too, may be (forecast from the same facts. If any of the radium minerals exist not only in the earth's crust but also throughout its interior, the earth must be slowly gaining in heat, and an uncomfortable possibility of this is that the earth, may on some distant day explode with violence.

Earthquakes and volcanoes may also find an explanation from the heat of radium, minerals in tha earth's crust.