Having been twice driven back by heavy south-western gales, Her Majesty's ship Beagle, a ten-gun brig, under the command of Captain Fitz-Roy, RN, sailed from Devonport on the 27th of December, 1831." Thus, 170 years ago today, did Charles Darwin begin his Journal of the Voyage of the Beagle, a personal account of that historic five-year voyage of discovery, which provided the material for his revolutionary ideas on natural selection.
Darwin was born in February 1809, and his student years were inauspicious. He was sent to Edinburgh to study medicine, but dropped out after a short time. Then he was diverted to Cambridge to train for the church, but there he paid more attention to the professor of botany, the celebrated John Henslow, than to the tutors in his own faculty. And it was through Henslow, though still only 22 and without formal qualification, that Darwin was recommended for the post of "gentleman-naturalist, victualed but without pay", aboard the good ship Beagle.
As a keen observer of all natural phenomena, Darwin did not neglect meteorological matters in his Journal. On one occasion in Chile, for example, he gives a good description of orographic cloud: "I was often interested by watching the clouds, which rolling in from seawards formed a bank just beneath the highest point of the Corcovado. This mountain, like most others when thus partly veiled, appeared to rise to a far prouder elevation than its real height of 2,300ft. The cloud was seen to curl over and rapidly pass by the summit, and yet neither diminished nor increased in size."
Returning to England in 1936, Darwin spent the remaining 46 years of his life in productive isolation in the wilds of Kent, visited only by a handful of fellow scientists. But the theories he developed during that period, more than any others from Copernicus to Freud, were to play havoc with conventional beliefs.
His ultimate conclusion, that we are all descended from "a hairy quadruped, furnished with a tail and pointed ears, and probably arboreal in its habits", was met with wrath and ridicule, particularly in theological circles where it disturbed a number of time-honoured and comfortably held beliefs.
But The Voyage of the Beagle itself was uncontroversial. Typical of its conclusions was: "What a difference does the climate make in our enjoyment of life! How opposite are the sensations when viewing black mountains half-enveloped in clouds, and seeing another range through the light blue haze of a fine day. The one for a time may be sublime; the other is all gaiety and happy life!"