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Southland Times, Issue 597, 28 November 1866, Page 3

rirj.'-'j.-i i •■ -' ■ ■ = Electricity fro^i Heat, Convertibility of Force. —lf electricity will afford us light and heat, so heat applied to various will give us electricity. Since Seebeck, in 1822 found that an electric current was generated hy heating the junction of two dissimilar metals, thermoelectricity was simply a large abstract addition to our knowledge without practical value until Nobili found that the thermo-electric pile, connected with a was a thermometer of wonderful delicacy. But it is now ascertained that its primary value as a source of dynamic electricity, was wholly undeveloped. Our readers are of course aware that the thermo-electric current is due to a difference in temperature between the two opposite faces of the elements of the pile. Marcus of Vienna was the first to obtain the electric spark. He constructed a powerful thermo-electric battery from an alloy, for the positive metal, of copper, zinc, and nickel; and for the negative, antimony, zinc and bismuth : the elements of this battery were so arranged that their lower junctions could be heated by a row of gas jets, while the upper were cooled by a current of water. The electro motor force of one of these elements was equal to 1.35 of a Bemsen cell. Six of them are sufficient to decompose water rapidly, and melt a fine platinum wire. The conversion of the heat into electricity was shown by the fact that the water used for cooling the upper junctions of the

couples was much more rapidly warmed when the circuit was broken than when closed. More recently Professor Wheatstone has constructed * a strong chromoelectric battery, composed of sixty elements, connecting the terminals of this battery, a brilliant spark was obtained, and platinum wire fused. Water was decomposed and electro-plating done, in fact, all the effects obtained from a small voltaic combination were reproduced with ease. The electro motor force of this battery was equal to two of Daniels' cells. These recent experiments seem to show that thermo-electricity is destined to play a far more important part than it has" hitherto done. The great constancy of the current will be one of the chief arguments in its favor. Like windmills, thero-electric batteries might be erected over the country, and entrap— finally converting into mechanical motion and thus into money— -the gleams of sunshine, which would be as wind to the sails ofthe mill. If this can be so, what a store of power is constantly wasted by the non-use of the solar rays poured on the desert. Can we not utilise this with the thermoelectric battery ; can we carry the force of Sahara's sun through wires to Cairo, and make it burn in Greenland ? The future must answer. Let England not he disheartened by anticipated destitution of heat from the exhaustion of her coal-fields.