6 Charles Darwin – The Voyage of the Beagle
In December 1831 the Beagle sailed from England in a voyage that would
circumnavigate the world and last nearly five years. This Royal Naval vessel was a
hard-working 10-gun brig, 90 feet in length, and with a crew of 65 men commanded
by Captain Robert FitzRoy. The object of the voyage was to complete the survey of
the coastlines of Patagonia and Tierra del Fuego undertaken during the first voyage
of the Beagle from 1826 to 1830 and to survey the coastlines of Chile and Peru.
The Beagle was also ordered to circumnavigate the world and measure an unbroken
chain of times and thus longitudes at specific ports around the globe using the Royal
Observatory at Greenwich as a reference point. The invention of an accurate marine
clock by John Harrison some decades earlier allowed the measurement of local time
compared to another clock measuring the time at Greenwich. Since the earth revolves
360 degrees of longitude in 24 hours, the time difference can be used to calculate
longitude at any point on the globe. Harrison’s marine chronometer revolutionized
navigation and greatly increased the safety of sea travel. Different watchmakers had
tried making his chronometer and for this voyage the Beagle was equipped with
twenty-two marine chronometers to test their efficiency and reliability in their long
voyage around the world. Sixteen were provided by the Admiralty and in his pursuit
of absolute efficiency Robert FitzRoy provided another six at his own expense.
FitzRoy employed an instrument maker, George James Stebbing, to look after the
chronometers, his only job was to ensure they were regularly and properly wound
and no one else was allowed into the chronometer room. No vessel had been better
equipped with a set of chronometers than the Beagle, and Captain FitzRoy was able
to write in his final report to the Admiralty that he had established a connected chain
of meridian distances around the globe, the first time this had ever been accomplished
by means of chronometers alone.
Robert FitzRoy was born in 1805 into the upper echelons of the British aristocracy
and their tradition of public service. Through his father, General Lord Charles FitzRoy,
Robert was a fourth great-grandson of Charles II. He entered the Royal Navy College
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