CORRESPONDENCE

Te Aroha News, Volume XIV, Issue 2105, 21 May 1898, Page 2

CORRESPONDENCE

Under no circumstances whatever is the Editor responsible for mutter contained in correspondence } (jTo the Editor.};

Sir, —A desire-fo lighten our darkness has at last come to the fore.. And none too- soon:. Lighting by means of candles or by kerosene is somewhat antiquated. Goal gas, none too modern as a lumihant, has its supporters.. Electric •lighting' is to be' reported on, we are told. There' is. a third up-to-date method about. much little has been said, because perhaps little is known of it looally. Ghn-you; sir; or any of; the- readers of your journal, give any informatien. concern? ing acetylene gas ?—I am,, etc:,. Light.: To Aroha, 16th, May,*lß9B!

fTThe fdllowing short article entitled: ‘ Itocentfacte about Acetylene,! taken from. ' The Cosmopolitan.’ of November, hß97^'may be ofinterestto ‘Light’’ and: others.]! ‘ The ease with- which: it cam Be' liquefied; and. reconverted; into aga&ded: at first to the conclusion, that it might be conveniently kept in: the liquid forin» andi converted, into' gas- as needed; Ihvestigatioßs since made by Berthelofe prove that the liqpid gas under, pres? sure, as in- tanks; is explosive;. The explosion* may be brought about by a. spark or any sufficient elevation: of;' temperature; The gas itself,, under a; pressure, greater than*, about two atmospheres,, is- explosive- -in. the same way. There have-been a number of instances inwhSch the substance, under the conditions just cited, has exploded, in several! - cases- with-; terrific- results,. The explosionsv here referred to are independent of the presence of; and are due to the endothermic nature of the-gas. It is also established, that at atmospherio pressure a mixture of three per cent of acetylene gas with air. is, explosive,. and such mixture conrtinues explosive until : the acetylene exceeds, eighty-two per cent; of the mixture; The corresponding numbers for common coal-gas are eight and. sixty-two per cent.. On account of its explosive properties the use of. acetylene has been prohibited in Germany Acetylene is heavier than coal-gas,. and would,, when escaping by a leak, diffuse much? less mpidly than common, gas,, and thus would sooner bring, about an explosive mixture near-the leak. From, some ex* porimentalresults of: Professor Jacobus of Hoboken, recently, made publiedt appears that the light from acetylene gas shows certain.colours, especially flesh tints,, more nearly as daylight than does any other artificial light. He-also verifies the fact that for burners using the same amount of common gas and? acetylene, the acetylene burner produces tern times as much light as does the common fiat gas burner, and nearly three times as much as the Welsbach burner, Fromcareful considerations and computa.. tions Professr Jacobus finds that for equal light in New York City, from the incandescent electric lamp, the ordinary gas burner and the Welsbach burner, the respective costs are as I, .5, .17*- To compete with ordinary gas when used in a Welsbach burner, calcium carbide for acetylene manufacture would have to be furnished in New York at nineteen dollars and fifty icents per ton. Whether this can be 'done has not been, decided. The same -authority concludes that if is unwise ;to use acetylene gas under pressure or iin the liquid form, and that though Hhis-gas may be more expensive than tother illuminants, it will probably have :its fields of usefulness because of its properties, jpefc as the incandescent electric light holds its place -against gas in New York, though it is twice as expensive as gas-light from the common burner. There are many .other considerations- which affect the yalue of an illuminanfc besides its icost.’*