There are two types of people in the world: Patrick O’Brian fans, and people who haven’t read him yet. This second category includes many women who are put off by the seemingly excessive focus on ships. This worried me, too. I thought it would be all battles and no women: perhaps even (shudder) a seafaring Lord of the Rings.

I have travelled the seas with Captain Jack Aubrey and Stephen Maturin and, I hope to tempt you to set sail on the “Aubreyiad”. I won’t deny that there are mentions of futtock shrouds, bowsprits and even main-studding-sails (just don’t try to say this out loud). Each of the novels begins with a diagram showing the 21 sails of a square-rigged ship. This may give the impression that you need to know – indeed care – about such things. This is only true to the extent that, to enjoy an episode of ER, you must understand the full implications of: “give me an ABG, CBC, chem 7, cardiac enzymes, and coag panel”. It’s possible to let it all wash over you – like the fast-talking political detail in The West Wing, or the slang in The Wire – and form a general impression of whether the wind is causing problems or the French ship is about to sink. (On the other hand, you could consult A Sea of Words, one of several guides to Jack’s world.) O’Brian is never heavy-handed with his research: it’s simply that the books are set in a perfectly realised world, which happens to be a ship at war.

There is vastly more to Jack than fair winds and rigging. For one thing, there is Stephen, the brilliant, bold, enigmatic Irish-Catalan naturalist-surgeon-spy. Although O’Brian doesn’t write up his physical charms, I’ve got a huge crush on Stephen: he is obsessional and secretive, but also fiercely intelligent, moral and passionate. For book after book, I willed the gloriously lithe Diana Villiers to succumb to his pursuit.

The cornerstone of the series is Stephen’s friendship with Jack, masterly with his ship, oddly “at sea” on land. Each man has their sphere of genius and their blind spots. Jack’s brilliance is an instinct for getting the best out of his ship and his crew. He has a reputation for being “lucky Jack” when it comes to the enemy at sea, yet on shore he dodges bailiffs and cuckolded husbands. Stephen identifies tens of new species on his travels, conducts an impromptu trepanning on deck and provides vital intelligence to the Admiralty, yet he has to be helped aboard ship to avoid falling in the sea. Stephen learns new languages with enviable speed, yet he can never master the vocabulary of navy. This is helpful: ship business is the often explained for his (our) benefit.

Naval convention dictates that, while the men of the lower decks have just 14 inches each to sling their hammocks, Jack must live as a hermit in his (comparatively) large cabin. Stephen’s presence on the ship gives Jack the rare contentment of travelling with an equal, one who doesn’t need to wait for the captain to initiate conversation.

It’s not all plain sailing between them, as it were. (Incidentally, I never realised how many common terms derive from the navy: show your true colours, all above board, by and large, the cut of his jib, in the offing, toe the line, under the weather, overbearing, take the wind out of his sails.) There is conflict over women, over the cages of exotic species that fill Stephen’s cabin and, most frequently, the driving sense of urgency to be somewhere else. Time after time, there is “not a moment to be lost” and Stephen misses the chance to gather, say, bats in Brazil as they give chase to a possible prize. These differences of opinion are resolved not through duels, but rough and enthusiastic duets in the captain’s cabin, Jack on the violin and Stephen on the cello. It’s one of the great partnerships of fiction.

The detail of the world of the ship is wonderful. It’s a complete and distinct society. There are boys from the gentry put to sea aged nine, as Jack was, aiming for the distant rank of captain; young men from Malaya and Plymouth; old men from London and Java. Three hundred of them trapped on the ship, challenged by storms, calms, bad food, the French and each other. What really makes O’Brian nothing like Tolkien is the humour. The sailors’ indulgence of Stephen’s hopelessness with all things naval, Stephen’s wry reactions to peculiar sea habits, the droll not-quite-insubordination of Jack’s steward. Jack’s mangling of languages, Stephen’s persistent bewilderment at naval customs. O’Brian skewers the pompous in their own words. It’s Jane Austen at sea. And yet, somehow, I’ve so far failed to convince my mother – Sue Birtwistle, Austen admirer and producer of the TV serial Pride and Prejudice – to dip her toe in the water.

So, please, don’t judge these books by the cover pictures of sailing ships. The centenary of O’Brian’s birth will be 12 December, and what better way to mark it than by opening Master and Commander for the first time? (Actually, Patrick O’Brian was born in July 1945 when Richard Russ changed his name by deed poll and buried his previous life. But that’s another story.)

If you do attempt them – weigh anchor, if you like – you are likely to be grateful rather than daunted by the fact that there are 20 books in the series. (My record is four in a week, while travelling in Costa Rica with a friend who liked to go to bed early.) You may even go as far as cooking one of the recipes from Lobscouse and Spotted Dog (“a gastronomic companion to the Aubrey-Maturin novels”). Iles Flottantes in the shape of the Galápagos, anyone? You will soon forgive the broadsides and fo’c’sles and, like Stephen, come to love this wet and wooden world.

• Patrick O’Brian A Book of Voyages is reissued this month by HarperCollins.