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Show H It I i tao ."lint Arr-uri'" Instrument Do H vJhlh! liy Man. m A elironometcr !s the most nee urate H instruinrnt deviswl by man. Thegrrea B or part nf the chrnnomctpr'amcchnuiiiin B reseiuhiec that of the common v.atch, M but i constructed ith every possible B rovis!on t6 insure accuruey, and ao per- B feet is the instrument that even tu, far H bael; as 1720 Mr. irarriwon prwlueed a B chronometer which did not vary n ee- B ond in ton years. Everything has leen : done in the manufacture of this marvcl- B oils piece of mechanism to avoid error B that human ingenuity can device. Per- B hap.s the most w onderf ul feature of the H chronometer i 1 lit- compensation lwl- H ance, a beautiful contrivance for eoun- B teractinr the olT.nt of changes of tem- B perature, wldeb, by causing an ordl- H nary balance to expnnd and contract, BB bring about variation of time. So henutifully i the lmlance maintnitied that a ship may (hiss from the torrid one to the neighborhood of tlitt pole it- f.elf, and f lie elij-onomet.r will not vary a second. . ... |