Science Sittings

New Zealand Tablet, Volume XXXVI, Issue 8, 27 February 1908, Page 35

Science Sittings

To Photograph the Air. x An important discovery has been .made by an assistant of the Meteorological Institute, Chrisfiiania, E. Russeltvedt, who was formerly manager .of the tforth Light Station, Spitsbergen. M. Russeltvedt has succee~ded in constructing a self-registering instrument for photographing air and' electrical phenomena. This discovery caused a great sensation, and the results will shortly be published. Fireproofing .Wood. , / The process of fireproofing wood very much resembles embalming. The wood is first relieved of its saps and juices, which are leally its blood, and a preservation fluid is injected to ta-e their place. The planks to be fireproofed are put into a .sort of boiler or digester. This is closed, and steam at a low pressure is run into the digester and the wood parboiled for" from one to fifty hours. This is. to soften or loosen the dry saps or juices in the fibre. After the steaming process a powerful vacuum .pump draws the saps and juices from thet wood, leavimg a finely-divided cellular structure. Next the fireproofing solution is pumped into the chamber, the absorption and saturation being assisted by the partial vacuum. A pressure of from 80 to 200 lbs a Square inch is' next applied and maintained until the absorption is complete. After -draining off the excess solution the wood is withdrawn and thoroughly dried in a kiln, with the result that the interior cellular wood structure is left filled with minute crystals of fireproofing salts. The Use of Windmills. The windmill i® nob yet superseded as an engine driven by this power of ' unbougiht wind,' (says' the 4 Manchester Guardian.') In Holland they are used for sawing timber, cutting tobacco, grinding trass and ■draining the polders. Holland has 10,000 windmills, each of which is said to drain 310 acres of land, at the average cost of one shilling an acre a year. In Norfolk they have been of inestimable service for works of drainage on the marsMands. A 15 horse power windmill erected at Faversham raised' in ten months 21,000,000 gallons of water from a depth of 100 feet, saving 100 tons of coal. In the United States iron s eleton windmills were employed to pump water for domestic purposes Lrog before they were employed for irrigation work.. Powerful mills h a ve given farmers living) on the plains a ch2an source of power for various purposes, among other things to 'introduce town luxuries into their homes . Heat, Power, and Light from the Earth. As the exhaustion of the fuel supply of the world becomes more acutely realised as an inevitable prospect, men of science are taking into view with increasing! seriousness whit has . been but a dream till now, the possibility of drawing upon the interior of the earth for the energy which, whether in the form of heat, power, o r light, is required for the welfare and convenience of mankind (says 4 The Technical World.') Whin it is considered that the cool crust of the plan- 1 et on which we dwell is thinner, t relatively in ' size, than the shell of an egg, and that at a depth of only 25 miles, all substances are molten, the temperature, being something li c 10,000 degrees, it seems absurd that we should indulge anxiety about an available heat, supply for .the future. There are places "where the shell of the globe is -very much thinner, and where the hot core is so near the surface that conduits reaching•downward might easily be constructed by human' ingenuity. Of course it would not be practicable to bore down into a region of molten roc v s, but pipes could be " sunk a sufficient distance to reach strata of as high a degree of iheat as might be desired. Prof. Wm.. Hallock ' of Columbia University" says that the putting down of such .pipe would not cost more than £2000 per mile, ad he offers the . suggestion that, merely for experimental purposes, it miajht be worth while to spend £10UOO in smiting two pipes .to a depth of i 2,000 feet. A connection having been, established between the. lower % *£l!? * pi ? e » an inexhaustible supply of heat could be fetched to the surface.