Science Siftings

New Zealand Tablet, 13 April 1911, Page 691

Science Siftings

BY ‘VOLT*

Lifting Magnets. < The advantages of lifting magnets for handling all kinds of loose materialpiles of turnings and other scrap, castings of awkward shape, rails, etc., requiring to be compactly bound in order to be handled by a crane, have won rapidly increasing recognition of late. At the plant of the United States Steel Corporation at Gary, Indiana, lifting magnets are in use capable of lifting the entire top layer of a pile of sixty-foot rails, with an aggregate weight of fifteen tons. An Interesting Experiment. Messrs. Barclay, Currie, and Co., the Clyde shipbuilders, are constructing for a Continental line a vessel which will revolutionise shipping. It is to be a 12-knot boat of 5000 tons gross, driven by internal combustion engines of the Diesel type, hitherto only applied to trawlers and yachts. One hundred tons of crude petroleum at 34s to 40s a ton will do the work of 300 tons of coal. It will require , only half the usual engine and boiler space, onefourth the bunker space, and will dispense with from 50 to 75 of the stokers. The vessel will have no funnels. The ship will be an exceedingly interesting experiment in construction. If it is found possible to drive great vessels with petroleum safely and swiftly, the coal-owners will suffer, and Mr. Rockefeller’s millions will increase faster than ever. An Electrical Test. Science has found a method of detection of the bogus paralytic. For example, long after a broken arm is healed, the patient may assert that he is unable to use the arm properly. It is then the duty of the physician to find whether a real paralysis exists, and_ where. Electrical energy may bo compared to psychical energy, the battery to the brain, the wire to the nerve, and the electric bell, for example, to the member moved. A muscle contracts hen a current is applied to the corresponding nerve. If the muscle on the affected side of the body reacts as strongly as the corresponding muscle on the opposite side, the partial paralysis is simulated. If the muscle on the wounded side reacts less strongly than, its fellow, there is a real disease of the nerve. Finally, if the muscle on the wounded side reacts more strongly than its fellow, the seat of the paralysis is the central nervous system, the brain or the spinal cord. In Arctic Waters. . Through investigations carried on from vessels visiting Arctic waters it has been proved that the polar water, which is protected by a thick layer of ice from the influence of light, accumulates matters which have a fertilizing effect upon the vegetable life ,in the open sea and which in the cold dark polar waters are not used. The polar > basin is like a large tract of fallow land in which fertilizing matters accumulate without being used. The warm water of the Gulf Stream, on the contrary, when reaching the northern part of the Atlantic might be called desert water, as its vegetable life has been so exhausted that it contains only scanty means of subsistence for any animal life. The more the polar water mixes with the warm water of the Gulf Stream, the more luxuriant seems to be the growth of the higher marine life. It is the cause of colder summers in Northern Europe, but the fisheries seem to be better in proportion. The result of these investigations indicates a possibility of foretelling good or poor fishing seasons, and the explanation of many interesting and unusual things that are dependent upon the temperature of the northern section of the Gulf Stream. Ancient Roman Pottery. A German scientist claims to have discovered the secret of the method employed in the manufacture of the ancient Roman pottery. This, it is declared, lies not in the chemical composition of the paste, but to the treatment applied to it and to the colored glaze. The clay was prepared by ageing, followed by washing, kneading, and stamping. Before firing, the ware was exposed to the sun and air, but sheltered from rain until it appeared quite dry. The frequent changes of temperature and humidity and the alternation of sunlight and darkness which occurred during this slow process of drying insured uniform shrinkage in firing, and durability of the finished ware. When a glaze was used it was applied to the moist ware immediately after the latter was shaped, so that the glaze became intimately united with the body of the ware during the slow drying process. Firing then produced a brilliant • gloss and imperishable colors. It is odd that the secrets of the ancient potters should in many cases far outclass the modern. The Zungi Indians of America can make a pottery that no modern kiln can imitate. Doubtless it is through some such secret as that learned by the German savant.