WORK OF SCIENCE

Evening Post, Volume CXVIII, Issue 35, 10 August 1934, Page 16

WORK OF SCIENCE

RECENT DISCOVERIES

RUBBER AND BEANS AS FUEL

MAGNETISED, METALS

The drought in- .parts .of -North America and Europe is • the severest which has been recorded. This might suggest that the world's total rainfall is decreasing. But there i.s no other, obvious evidence for a decrease. The amount of 'water in the. rain that falls on the dearth's surface must be equal to the amount of water that evaporates into the atmosphere. As tho amount of evaporation depends on the heating strength of the sun's rays, a variation in it must be duo to a variation in these rays. While such variations may exist, they have not been detected by physical observation. The more exact the observations the more constant the sun's radiation appears. But if the total annual rainfall remains fairly constant, where is tho rain falling? In America it seems to be falling during hurricanes in the AVest Indies. , The number of hurricanes occurring there during 1933 is tho largest that has been recorded in one year. In a note in "Nature" it is pointed out that severe. Central American hurricanes have started in 1934 at the unusually early, period of the. first half of June. On June 13 the town of Octotepcquc was entirely destroyed by a storm, accompanied by exceptionally heavy rains and floods, which passed across Salvador before reaching the Mexican coast. | NEW FUELS. " Students of sociology will note* the development of a curious application of scientific research. Investigators are now trying to discover the, best methods of using agricultural products, such as rubber and soya beans, as engine fuel. It is reported that the Ceylon Government Railway is using fairly large quantities of scrap crepe rubber in firing steam engines. The rubber is added to the wood and coal, and makes them burn more quickly with less attention. Old motor tires arc said to do particularly suitable, because of their cotton foundation. Attempts arc being made to distil a fuel oil from rubber. Tho chief difficulties' in all these experiments aro provided by fhi residues that foul furnaces and cylinders. One vould imagine, . too, that disagreoable smells will not easily be avoided. The engineering staff of the Chineso Eastern Railway arc experimenting with blends of shale oil and soya bean oil as a fuel for internal combustion engines. The governors of Manchukuo hope that tlie imports'1 of petroleum can be reduced by the successful utilisation of fuel prepared from local products. TREATMENT OF METALS. E. G. Herbert, of Manchester, 'has discovered aifd applied some remarkable properties of metals. When metals arc heated, or magnetised, or cold-worked, they, aro thrown into a. state of slow vibration, which is manifested by a periodic variation hi, hardness. "The period of the fluctuations may "vary freni twenty minutes-to an hour for hot metals, and to about six hours for cold metals. This means that at some times tho-metal is'harder than at others. Herbert finds that it is pbV sible to stop the slow vibrations at any moment by placing the metal in a strong magnetic field. If the moment is chosen when tlic hardness of the metal is at a maximum the.inet.al will remain in. a. condition of maximum hardness. Herbert ; regards the fluctuation b'i hardness in the metal as due to an electromagnetic oscillation of extremo slowness : and stupendous wave-length. A . long radio-wave has; a length of twenty miles and a frequency of about ten thousand ' vibrations per second. The length of the wave associated with the fluctuations in metallic hardness would be about one thousand million miles if its frequency is about six hours. The heated metal apparently emits this long wave through its slow fluctuations. Herbert ascribes the fluctuations to periodic changes in the electromagnetic force of cohesion betwecu. the crystal slip planes oil which deformation takes, place under the influence of pressure. HIGH PRESSURES. The progress of science depends on a knowledge of the properties of matter especially under extreme conr ditions. Keeont knowledge of the structure of atoms has been obtained from the.behaviour of particles moving at extreme speeds. In tho interior of the earth and tho stars matter exists at very high pressures and temperatures. . Tho experimental reproduction of similar conditions on the. earth's, surface is exceedingly difficult. Bamaaucr has suggested an ingenious method of experimenting with gases at high pressure. A bullet is - fired from one gun so that it enters the barrel of another 'gun. The gas in the second barrel is compressed into a very small volume. The bullet carries a projecting gold hook. When it has pushed the gas into the. closed end of tho barrel, the' gold hook will be bent, and the amount of bending, will show how near it aproaehed the closed ond. This will give the volume of the gas at maximum, compression. The quantity of tho gas, compressed can be calculated from the amount originally in the barrel and the amount which leaks past the bullet as it flies up the barrel. : GROWTH OF BUGS. V. B. Wigglesworth has , made- some investigations on the growth of bugs. The bloodsucking bug can moult after one meal.' The interval from the meal to the moult is of a definite length. After five moults teh insect becomes adult. This last moult is usually described as the metamorphosis and occurs about a month after tho last meal. If the insect is decapitated soon after feeding it will not moult, though it may remain alive, headless, for eleven'months. If it is decapitated seven or more .days after feeding it will moult. This shows that the moulting must be controlled by a hormone in the head. If the blood from an insect decapitated more than 'seven days after its' last meal is circulated in an insect decapitated less than seven days after its last meal, moulting is produced in the latter insect. Similar experiments /made with bugs during the periods of tho earlier moults'show'the presence of another hormone in the head, inhibitory to metamorphosis. When the effects of this hormone are evaded, the bug is transformed directly into an adult.