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Show CHRONOMETER PUT TO TEST It Is Kept on Ice to Secure Accurate Adjustment. Each yew the tlmn ihi onometers of the United States navy aro sub-jested sub-jested to a test to determine their ac-Ihir&cy ac-Ihir&cy and to correct any Irregularities. Irregulari-ties. This operation ' commences in January and usually lasts until tho mlddlo of Juno, nnd during that time theso delicate timepieces nro kept oa ice nt tho United States naval observatory. observ-atory. It is not for any fear that thoy will spoil that they aro subjected subject-ed to this frigid experience, but it is r.eceesary for tho purposo of accumie adjustment that they should all bf mclntulnod In a constant temperature. Tho necessity of having n ship's clocks all absolutely nllko will bo real-iced real-iced by tho layman when ho Is ro-n.lnded ro-n.lnded that an error of four seconds in tho chronometor means an error r n mile in calculating tho vessel's lot. tlon. The temperature varies at different dif-ferent times of tho tost from CO to 90 degrees nnd tho losing or gaining qualities of tho chronometers under tneso conditions nro accurately kept. Thus with n chart expressing In curves Just what ho may expect from his chronometer under different conditions condi-tions of cllmato, nnd, with his thermometer ther-mometer and barometer close at hand, n sailing master may calculate to a nicety tho correct timo and get his location to a cortulnty. |