There's a naval engagement looming this summer, a ship-to-ship duel straight from the days of fighting sail. But it will be fought out in bookstores rather than on the high seas, and the combatants will be flinging sagas at one another rather than cannonballs.

Up to windward there's publisher W.W. Norton with author Patrick O'Brian on the quarter-deck, ready for the late-summer publication of "The Hundred Days," the 19th title in his series featuring Capt. Jack Aubrey and seagoing companion Stephen Maturin.

But sailing on a course to intercept is publisher Little, Brown, which is relaunching author C.S. Forester's classic 11-volume naval adventure series with hero Horatio Hornblower.

Below decks, in the publishers' magazines, publicists and marketing directors are putting press kits together, placing advertising orders, and pitching to booksellers.

But other than that both series are written by Englishmen and involve fictional British naval commanders during the Napoleonic Wars - and are vastly popular - there's a lot of sea room between the two. The plotting and the style of the two series are as different as a 19th-century frigate from a nuclear submarine; the personalities of the two commanders are such that it is hard to imagine them enjoying each other's company. And, by and large, the readership is different.

The Hornblowers, said William Fowler, president of the Massachusetts Historical Society and an authority on the naval history of the period, "are boys' books," adding, "And boys come in all ages."

And while there are men who read the O'Brian books, said Starling Lawrence, his editor at Norton, "they get fidgety when he's not banging away with great guns."

To a far larger extent than with the Hornblowers, the O'Brians have attracted women readers - for the same reason, Lawrence said, "that they read Jane Austen." There is the same interest in the social customs and conventions of the day, and it's not surprising that O'Brian considers Austen the greatest English writer.

"One of the things we had to worry about" when Norton began publishing the O'Brians in 1990, said Lawrence, was how to capture readers who had grown up on Hornblower (Forester's books were published between 1937 and 1967) "without

portraying them inaccurately as son-of-Hornblowers."

The Hornblower books invariably begin with Hornblower aboard his latest command, or impatiently waiting to head there. (Once, he is in a French prison, plotting an escape.) But O'Brian is often a third of the way into the story before Aubrey and Maturin even climb aboard, having spent 100 or so pages in various intrigues, romantic and political - although in the forthcoming "The Hundred Days" Aubrey is in action against Moroccan pirates by Page 57.

"They're frustrating ... because there's so little action," said retired commander Tyrone G. Martin, former captain of the USS Constitution. "They're much more literate, but they're not good navy stories."

When Hornblower takes his ship into action, cannons belch, masts topple and men are killed and wounded - often horribly so. Forester's battle scenes are so vivid, said Fowler, a former professor at Northeastern University, that he used them in his naval history courses.

But in an O'Brian, said editor Lawrence, "You think you're leading up to a great battle, but it doesn't happen, because Maturin is down in the orlop tending to the wounded. He's hearing the thumps and crashes on deck, but it's only 20 or so pages later, when they're having dinner in Aubrey's cabin, that you learn what happened."

As the books' focus differ markedly, so do the literary commanders.

Martin, a destroyer commander who served during both the Korean and Vietnam wars, says he'd much rather have served under Hornblower than Aubrey. "There's a certain slovenliness" to Aubrey, he said, "a greed, a lust, a venality, a ragged edge."

But Hornblower, he said, would be "a role model" for young officers. And, agreed Fowler, "I can't imagine a midshipman being told to be like Aubrey."

Of course, said Fowler, the worldly Aubrey "is the kind of guy you'd like to have lunch with," rather than the "taciturn and rigid" Hornblower, whose occasional wardroom dinners were best-behavior experiences for his junior officers.

For all their differences, both series have been tremendously popular.

Norton editor in chief Lawrence says the O'Brians have sold between 2.3 million and 3 million copies in hardcover and paperback since the first book was published in late 1990. (They began appearing in Britain in 1969.) Little, Brown associate editor Amanda Murray, citing the fact that the Hornblowers go back some 50 years before sales records were computerized, said there is "no way to tell" how many copies are in print.

For the Hornblower relaunch, Little, Brown has commissioned fresh covers from illustrator Douglas Smith, who was so much of a Hornblower fan, Murray said, that he already "had a Hornblower illustration in his portfolio."

In the publishing wardrooms where the grand strategies are mapped out, the success of the O'Brians is credited with heightening interest in the genre - even by editors and publishers of O'Brian rivals like Murray, who is steering the Hornblower relaunch at Little, Brown.

Over the publishing horizon, Holt/Owl is promoting its new Hearts of Oak paperback reprints of classic sea adventures, both fiction and nonfiction. Alexander Kent's series featuring the Hornblower-esque Richard Bolitho has a new American publisher, McBooks, Alexander Skutt's small upstate New York house, which is branching out - quite far out, in fact - from vegetarian cookbooks. O'Brian, said Skutt, "is reviving interest in the genre," and he is seeing "a really good response" to McBooks' reprintings of 19th-century sea classics.

Two American authors of recent naval adventure series are also acquiring a following.

Out this summer from Pocket Books is "The Continental Risque," by James L. Nelson of Harpswell, Maine, the third book in the only series to feature an American hero. Many readers, however, consider Forester's "Captain from Connecticut," his only book with an American hero, among his best, though it is long out of print.

Though Nelson considers his books "more in the Hornblower tradition," he did secure a cover blurb from O'Brian that reads: "Nelson writes with the eagerness of a young man sailing his first command." Two more books are scheduled in Nelson's series, which is set during the American Revolution.

Then there's Alan Lewrie, hero of Dewey Lambdin's series published by Fawcett. "The King's Coat," the first of the series and scheduled for a September reprinting, is also set during the Revolution, though viewed from the Royal Navy's side.

Norton's Lawrence thinks each series is "complementary to each other." Or, as Little, Brown marketing director Carl Lennertz quipped, "A rising tide lifts all boats."

Pub Date: 8/23/98