Meddelelser 2008 - Ole Rømers Venner

accurracy as tests on ships in 1768 and later have confirmed. The superiority of this
solution to the one by Harrison has been recognized most eloquently by R.T Could
who restored the H.4 timek*eper.u'
Le Roy's clock is the instrument on which the subsequent improvements of the
mechanical chronometer can be considered to be based. If we compare the
chronometers made by Harrison and Le Roy with the clock constructed by lsaac
Thuret according to Huygen's invention, the conclusion is clear. Essentially, Le Roy's
solution is a highly improved version of the Thuret clock with the escapement almost
free from the driving train and the balance adequately compensated for temperature
effects. These refinements may seem simple, but their development took almost a
century.
In conclusion, this historical perspective may have shown that much had to be done
by clockmakers rather than scientists before the promising protofype as a result of
Huygen's ingenious invention and Thuret's superior workmanship was transformed
into a chronometer suffciently accurate for measuring longitudes at sea. Giving up the
pirouette was the easiest step, already done by the watchmakers, followed by freeing
the balance from temperature effects and the escapement from coupling. Along this
route neither the remontoire nor the fusee had to be reintroduced. The clock resulting
from the cooperation of Huygens and Thuret did not represent a blind alley but was
the beginning of a promising development. We may be happy that, whereas all earlier
and later pendulum clocks designed by Huygens to solve the problem of measuring
longitude at sea have vanished, this balance clock has been preserved.
Postscriptum
As the list of notes shows, nearly all information in this article has been taken from
Christiaan Huygens' correspondence and the extensive notes added by the editors of
his Guvres Complåtes. As more recent research and/or discoveries may have yielded
results throwing new light on the collaboration of Huygens and Thuret on clocks in
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