The second voyage of HMS Beagle , from 27 December to 2 October , was the second survey expedition of HMS Beagle , under captain Robert FitzRoy who had taken over command of the ship on its first voyage after the previous captain committed suicide. FitzRoy had already thought of the advantages of having an expert in geology on board, and sought a gentleman naturalist to accompany them as a supernumerary.
At the age of 22, the graduate Charles Darwin hoped to see the tropics before becoming a parson , and accepted the opportunity. He was greatly influenced by reading Charles Lyell 's Principles of Geology during the voyage. By the end of the expedition, Darwin had already made his name as a geologist and fossil collector, and the publication of his journal which became known as The Voyage of the Beagle gave him wide renown as a writer.
Beagle sailed across the Atlantic Ocean , and then carried out detailed hydrographic surveys around the coasts of the southern part of South America , returning via Tahiti and Australia after having circumnavigated the Earth. While the expedition was originally planned to last two years, it lasted almost five. Darwin spent most of this time exploring on land: three years and three months on land, 18 months at sea.
At Punta Alta in Argentina he made a major find of gigantic fossils of extinct mammals, then known from only a very few specimens. He ably collected and made detailed observations of plants and animals, with results that shook his belief that species were fixed and provided the basis for ideas which came to him when back in England, and led to his theory of evolution by natural selection.
The main purpose of the expedition was to conduct a hydrographic survey of the coasts of the southern part of South America. This was a continuation and correction of the work of previous surveys, in order to produce accurate nautical charts showing navigational and sea depth information for the navy and for commerce.
