Science Siftings

New Zealand Tablet, 13 October 1910, Page 1683

Science Siftings

BY 'VOLT'

Signalling from the Eiffel Tower. At the Eiffel Tower in Paris they are now signalling time by wireless telegraphy to all vessels within a radius of 1800 miles. At present fifteen to sixteen horse-power is used, but a new installation will be made shortly, and then, as the engineers will have a 100 horse-power, the range will be doubled. A master clock is connected by wires with the key of the wireless station of the Tower. A Great Work. The Andes, that mighty mountain chain that extends the whole length of South America and divides it into two countries, has at last been pierced by a tunnel, which connects Buenos Aires on the Atlantic with Valparaiso on the Pacific. A resident of either city who wished to go from one place to the other was obliged formerly to make a four or live days' sea voyage, sailing three or four thousand miles, while now he can make the trip in thirty-six hours. Oil as a Fuel. The steel steamship Yale, a 22-knot passenger boat that plies between Mew York and Boston, has proved so conclusively the advantage of oil over coal for fuel that the boats of the line to which the Yale belongs will use nothing else for the future. It is not merely as a matter of economy, though there is a great saving, but it does away with smoke in the funnel, there is no noise or dust from coaling, and in the boiler room eight men do the work that required forty-eight. Interesting Experiment. An interesting scene was recently witnessed on a skating lake near a western city. White spots resembling air bubbles were noticed on the ice, and one of the skaters bored a hole into such a bubble and applied a match to it, whereupon a flame burst out at the surface. Further experiments showed that when a small hole was bored down to the bubble a long, thin jet of flame could be obtained which would last for a considerable time. The bubbles were due to accumulations of marsh gas, formed by the decomposition of vegetable matter at the bottom of the lake. Modern Balloons. The gas bags of modern balloons are made of a cotton fabric coated with India rubber in the most careful mannei, in order to assure perfect impermeability without sacrificing lightness. For all large balloons, and especially for dirigibles, two layers of cloth are Superposed and cemented together. The outer skin is covered with India rubber on one side only, but the inner skin is coated on both sides. As India rubber, even when vulcanised, is altered by exposure to light, the canvas is colored yellow in order to arrest the violet and ultra-violet rays, which are the most attractive. The pigment used in France is chromate of lead, which unfortunately must be applied to the canvas before it' is coated with rubber, and which consequently prevents the vulcanisation of the rubber because the chromate of lead is blackened by heat. Picric acid is free from this objection, but its employment is too dangerous. A Substitute for Celluloid. A new substance called ' resinite ' has been introduced in Germany, . and bids fair to replace celluloid in large measure. This material is produced in a variety of modi.fications by the union of formaldehyde and carbolic acid (phenole) in connection with certain metallic salts. The name is given on account of its resemblance in an important form to ordinary resin. This special variety is used chiefly with porous materials, such as wood, paper, pasteboard, etc., and renders them hard and impermeable. Thus ordinary pine wood when thoroughly impregnated becomes so hard that it rapidly dulls a planer. In another form it can be poured as a liquid into moulds. After coagulation it is transparent, with ruby tint, infusible, and unaffected by ordinary chemical reagents. It is well adapted for making ornaments, such as hat-pin heads, imitation jewellery; and for most-purposes where enamel or enamel varnish are employed. For doorplates, street numbers, signs, etc., it seems capable of rendering excellent service, being entirely unaffected by atmospheric action. A third modification is liquid, but upon the addition of a mineral acid it solidifies in a few minutes to an elastic, homogeneous substance, which can be easily cut, turned, polished, etc. In this form resinite can replace for a multitude of purposes horn, celluloid, vegetable ivory, and similar substances. Buttons, knife handles, mosaic designs, are some of the many objects made with this modification. When competing with celluloid it possesses the great advantage of being non-combustible. There is a large field for this new material in the glove manufacturing sections of Germany, where at present clasps are made chiefly from vegetable ivory.