The Beagle was sent on a surveying mission by the Royal Navy; initially it was intended to last three years but it was extended to five and the ship circumnavigated the globe. The captain, Fitzroy, wanted a companion on the voyage and through a convoluted series of events, ended up with a youthful Darwin along, which so annoyed the official ship's Naturalist who was also the surgeon (as was common), that he resigned and left at the first port of call, part way across the Atlantic. Fortunately another surgeon was appointed at the same port.

Very little of what Darwin wrote actually talks about the oceans...this is because he was no great sailor and spent most of his time aboard acutely seasick. Which, in turn, is why Darwin contrived to spend three out of five years on land!

All this and more is discussed in an excellent introduction to this edition, which has printed the 1st edition, abridging Darwin's journal by approx. 1/3, however. I'm not sure how to feel about that; have I been saved from really dull stuff that would have made what is a pretty lively book a chore to read? Or have I missed out on some interesting material? Weirdly, having made this 1/3 chop, the original Naval orders for the mission are included along with Fitzroy's essay attempting to reconcile the Bible (specifically the Deluge i.e. the Noah story) with contemporary geology. Even more weirdly both of these appendices are worthwhile. The mission orders are very practical and sensible and as specific as practicable and not, as I imagined they would be, vague and bureaucratic.

Fitzroy's essay reminded me of the kind of thing that went on in Oxford and Cambridge in the Middle Ages, where people devoted themselves primarily to attempting to reconcile reality with the Classical philosophers and the Bible, deploying a lot of casuistry and not much else for the most part. (Roger Bacon being a notable exception and look what happened to him - yep, locked up by he Church for practising black magic.) The fact is that even at the time of Beagle's voyage, it was clear that the Earth had to be orders of magnitude older than the historical record (with Genesis taken at face value) suggested and literal belief in the Bible, particularly the Old Testament, was crumbling amongst the educated scientists. Christianity itself was still axiomatic for most, however and Darwin no exception at the time as cannot be mistaken from this book.

Getting back to Darwin and his book, the Voyage is a rarely dull, often vivacious account not only of the flora and fauna Darwin encounters but also of the geology, people and societies he encounters, too, the latter providing most of the funny and dramatic moments, of which there are many. I cannot recommend it to people uninterested in geology and biology, however. Readers who cannot cope with such entries as a detailed theory of the formation of coral reefs (still considered correct as far as it goes, I believe) will get bogged down quite often. That said, anyone who has successfully waded through The Origin of Species will find this an easy ride by comparison.

Darwin displays an interesting blend of progressive attitudes (e.g. anti-slavery) and typical-of-his-day Victorian Christian notions (e.g. Christian Western Europe is the pinnacle of human societies) whilst observing on the many different nations and cultures he encounters alongside the wildlife and geology. Apparently the people of Tierra Del Feugo are the "least improved" on the planet.

What you won't find here is a theory of evolution, the question of the origin of species arising only a few times and then very obliquely and in passing.

In conclusion, nowhere near as important as Origin of Species but much more fun to read.