Free GMAT Reading Comprehension Practice Question

Standard accounts of how mariners solved the problem of finding longitude at sea credit the marine chronometer, a clock accurate enough to keep reference time through a long voyage, with a decisive victory over its rival, the lunar-distance method, which fixed longitude by measuring the moon's angular separation from a star. On this view the chronometer simply won because it was the better instrument. The story is appealing because it is clean: a precise machine displaces a cumbersome procedure, and progress follows from accuracy alone.

That narrative, however, understates how closely matched the two approaches were for decades. The lunar method, once corrected tables were published, was reliably accurate; its drawback was labor, since each fix demanded a sequence of calculations that few ordinary officers could perform quickly. Early chronometers were no less troublesome in their own way. They could match the lunar method's precision, but the first reliable examples were ruinously expensive, often costing more than a small ship's entire annual stores, and they were delicate enough that a single jarring sea could silence them. Accuracy, in short, was not the scarce quantity.

What actually tipped the balance, this account proposes, was neither precision nor elegance but cost and institution. As workshops learned to produce timekeepers in batches rather than as bespoke commissions, the price of a serviceable instrument fell by an order of magnitude within two generations. At nearly the same moment, naval administrations began issuing chronometers as standard equipment and training officers to rate and trust them, which converted a specialist's curiosity into a routine tool. The lunar method, never cheapened or institutionalized in the same way, gradually fell out of use. The chronometer's triumph, then, looks less like the inevitable reward of a superior design than like the contingent outcome of falling prices and administrative habit.