SCIENCE AND INVENTIONS.

New Zealand Herald, Volume XLVI, Issue 14109, 10 July 1909, Page 4 (Supplement)

SCIENCE AND INVENTIONS.

SHELL EXPLODES UNDER WATER.

Experiments at Toulon with the new French luminous shell show that an explosion can be produced at will either in the air or under water.... The illumination lasts 50 seconds, which is long enough to enable the marksmen to aim the next projectile. ; 3000-MILE WIRELESS. One of the highest telegraphic wireless stations in the world is about to be constructed by, the Navy Department in Rock Creek Park, Washington, for communication with warships at sea. It will be 600 ft high, and deliver and receive messages within a- radius of. 3000 miles. The cost & estimated at £60,000. ■; ■ r. ' ' \ NEW CABLE INVENTION. M'r. Henniker Heaton declared at the Imperial Colonial Club recently that he hoped that in a few months it would he possible to send- messages to every part of the British Empire at a cost of one shilling for twelve words. He added that he had the particulars of an invention ty which 60,000, words could be transmitted in an hour. VILLAGES IN VOLCANO. One of the most remarkable volcanic craters in the world'is that of Asosan, in Japan.. The outer crater is the largest in the world, measuring from ten to fourteen, miles in diameter. It is popularly said to contain 100 villages! Yet it is an active volcano, and eruptions are recorded in 1884, 1889, and 1894. The wall of the outer crater rises to a height of 2000 ft. . There is only one break in it, viz., that on the western side, where the river Shira-gawa issues. ■■ .';. ■ * /' # RADIUM TO BE CHEAPER, f A discovery which promises to cheapen by one-half the price ot radium and provide a valuable new source of supply has been made in Portugal. Seams of quartz, containing more than 50 per cent, of oxide of uranium, were discovered by Mr. T. V. Bower, a well-known engineer. Learning that remarkable health-giving properties were attributed to a. particular stream, he followed its course, and on the top of a hill found it ran over the yellow crystalcrusted quartz which he analysed as uranite phosphate. NO WAITERS WANTED. A iran who is fond of mechanical contrivances has had a dining-room fitted up with several tables, all of which have movable centres. The guests after they have marked the menu touch a bell, whereupon, the centre, of the table descends to the kitchen, ie there filled with the dishes required, and sent up again. The bell touched once more causes the centre to disappear again, when it is cleared and filled for the next course, and this procedure is carried on to the end of the meal. No servants are required in this singular banqueting hall. ~ ? . • "

THE TREATMENT OF FENCE POSTS.

It is estimated that a fence post, -which under ordinary circumstances "will last for perhaps three or four years, will, if given preservative treatment costing _ about sixpence, last, 18 years. The service of other timbers, such as railway ties, telegraph poles, and mine props, can be doubled and often trebled by inexpensive preservative treatment. To-day, when the cost of wood is a big item to every farmer, every stockman, every railway manager, to everyone in fact who must use timber where it is likely to decay, this is a fact which should be carefully considered.

EXPERIENCE WITH TURBINES. Speaking after a four years' experience of Parsons' marine steam turbine, i from a superintendent engineer's point of view,., Mr. C. J. Blackmore, of the Isle of Man Company, referring particularly to * their steamer, says that the small amount of trouble and anxiety involved in the maintenance of this class of engine, as compared with the big paddlers, has astonished him. The turbine steamer fdves no trouble whatever. She comes in and goes out, and nothing in the way of repairs is required throughout the season. Take this one item alonethe paddle steamer Empress Queen, of 10,000 indicated horse-power, which is still doing excellent work, is propelled by two wheels weighing together about 140 tons, the power being transmitted through two shafts 30in in diameter. The Ben-my-Chree is propelled by three screw propellers of the total weight of 4£ tons, the shafts being 9in in diameter. The disparity between the weights of the paddle-wheels and screwpropellers indicates to a very large extent the difference in . the trouble and cost of upkeep of the two classes of engines. In comparing turbine steamers with ordinary reciprocating twin-screw Channel steamers, there are two points in particular which may be noted in favour of the former : (1) Regularity of speed and economy of fuel in bad weather, the propellers being always well immersed and racing being quite unknown (2) capacity for developing the maximum power at any time without undue strain. The steam turbine responds at once to the increased demand made upon it whenever an extra push is required, whereas, when that time comes with a reciprocating engine, you have abnormal bearing pressures and choking of steam passages, which absorbs a lot of power and causes increased anxiety to those in charge. Only those who have experienced the stress of managing reciprocating engines when pressed to the utmost, limit can fully appreciate the contrast presented by the quiet, steady working of a turbine, and our best thanks are due to the Hon. C. A. Parsons for his worry-saving invention. A

SERVICEABLE PETROL GAS-LAMP.

The perfection of the incandescent gaslamp lias resulted in the more' extensive use of petrol vapour as a lighting medium, and various devices working on this principle have come into vague. "Certainly, when constructed upon rational lines, an inexpensive, simple, and highly efficient illuminant is rendered available.' One -of the beat of < these, yielding a light of between 80 and 100 candle-power, is of American origin, and owing to its safety has received the approbation of many of the fire insurance corporations on the American side of the Atlantic. Gas consumption is very low, one quart of petrol, costing about 3d, sufficing for some 15 hours. Each lamp is self-contained, and possesses the minimum of component parts, so that it cannot easily become deranged. The petrol feed to the burner, where it becomes vapourieed by heat, is by gravity, so that a uniform pressure is always maintained, and the flow of liquid can be adjusted to a nicety so as to secure the maximum of efficiency with the minimum of consumption. The lamp ie made in a variety of styles; it can be suspended from the ceiling, attached to a wall on a swinging bracket, or used as a table or stand lamp with equal facility. Owing to its construction, leakage is impossible, while it cannot catch fire, and even upon exhaustion of the reservoir the flame quietly dies out. It is an excellent device for rural districts, and affords an inexpensive and brilliant system of lighting for either the luxurious mansion or the humble cottage. Owing to , the fact that the reservoir is well removed from the area of heat radiation, the liquid is always preserved at an even temperature, and gas is only generated as required. . In the United States it has come into extensive use not only for indoor but also outdoor lighting, it being possible in the arc form to obtain a light of enormous candle-power at trifling cost. In this direction it should have an extensive field, since the lighting of our country villages, where public supplies of gas or electricity are not available, is deplorable. For such work an excellent pattern has been devised, the lamp, resembling that used in connection with gas in our town and city thoroughfares, being fitted with an external small reservoir. The lamp is stormproof, and is unaffected by cold weather, while it constitutes the cheapest form of street-lighting that has yet been devised. The possibility of obtaining a brilliant, steady light of 100 candle-power at less than a farthing per hour should give this lamp an extensive vogue.