Digitised sketches and watercolours by Conrad Martens have been placed online by Cambridge University library

On Christmas Day 1833, Charles Darwin and the crew of HMS Beagle were larking about at Port Desire in Patagonia, under the keen gaze of the ship’s artist, Conrad Martens.

The crew were mostly young men – Darwin himself, a recent graduate from Cambridge University, was only 22 – and had been given shore leave. Martens recorded them playing a naval game called Slinging the Monkey, which looks much more fun for the observers than the main participant. It involved a man being tied by his feet from a frame, swung about and jeered by his shipmates, until he manages to hit one of them with a stick, whereupon they change places.

The drawing, part of a short film made by Cambridge University, which holds the originals in a mass of Darwin material, shows the Beagle, the ship that helped change the history of science through Darwin’s observations on the voyage, and its companion ship the Adventure, at anchor in the background. Others, including a double-page spread, were made from the deck of the Beagle.

Alison Pearn, of the Darwin Correspondence Project – which is seeking to assemble every surviving letter from and to the naturalist into a digital archive – said the drawings vividly brought to life one of the most famous voyages in the world. “It’s wonderful that everone has the chance now to flick through these sketch books, in their virtual representation at the Cambridge digital library, and to follow the journey as Martens and Darwin actually saw it unfold.”

Darwin in his diary recorded the events of the day: “After dining in the Gun-room, the officers & almost every man in the ship went on shore. – The Captain distributed prizes to the best runners, leapers, wrestlers. – These Olympic games were very amusing; it was quite delightful to see with what school-boy eagerness the seamen enjoyed them: old men with long beards & young men without any were playing like so many children. – certainly a much better way of passing Christmas day than the usual one, of every seaman getting as drunk as he possibly can.”

Christmas two years earlier at Devonport, when the start of the voyage was delayed by bad weather and the crew could get at pubs and not just manly sports on shore, had been a very different scene. Darwin furiously recorded: “Monday 26th A beautiful day, & an excellent one for sailing, – the opportunity has been lost owing to the drunkeness & absence of nearly the whole crew. – The ship has been all day in state of anarchy. One days holiday has caused all this mischief; such a scene proves how absolutely necessary strict discipline is amongst such thoughtless beings as Sailors are.– Several have paid the penalty for insolence, by sitting for eight or nine hours in heavy chains. – Whilst in this state, their conduct was like children, abusing every body & thing but themselves, & the next moment nearly crying. – It is an unfortunate beginning, being obliged so early to punish so many of our best men there was however no choice left as to the necessity of doing it.”

It would be a further 26 years before Darwin published his theory of evolution, On the Origin of Species by Means of Natural Selection, based partly on wildlife observations he made on board the Beagle. The voyage, and many of the people he met and the places he saw can be traced in scores of tiny lightning sketches made in pencil and watercolour by Martens – although unfortunately he joined the ship too late to record the weeping and hungover sailors in their chains – which have been placed online by Cambridge University library .

Martens left the voyage the following year; there wasn’t enough room when the Adventure was laid up because it had become too expensive to continue the project with two ships, and the two crews combined in the Beagle. He settled in Australia, where he became a successful landscape artist, and sent Darwin the gift of a watercolour to congratulate him on the much-delayed publication of his great work.

Pearn described his drawings as a visual counterpart to Darwin’s letters home. “Both bring to life a really remarkable adventure, different landscapes, the lives of the local people and of the crew of these two tiny ships in a vast and remote part of the world.”

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