The chronometer of the Ilaria gains four minutes a day and never once stops. You must say which part is failing before opening it: stripped down without a diagnosis, it loses its certificate.
Three tests on the bench. No single one is enough; at least two are needed.
A marine chronometer gains four minutes a day and never once stops. Inside, everything looks right: the balance wheel swings, the pallet fork releases the teeth one by one and the ticking sounds as it should. But a faulty escapement sounds different from a sound one, and the test bench hears what the ear cannot.
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