POLONAISE By Jane Aiken Hodge G.P. Putnam's. 410 pp. $18.95

MY GREAT-AUNT Adelaide, when aged 82, was finally persuaded to cross the English Channel and visit Paris. I think we argued that she was no longer of an age to be debauched, upon which assurance she packed two rolls of toilet-paper, two packets of digestive biscuits, and went. She had a personal reason for going: she wanted to see Napoleon's tomb.

To my aunt, Napoleon was still The Ogre. She had been put to bed as a child with his bogey-presence as the threat to make her sleep, and her pilgrimage to the Invalides was almost certainly made to satisfy herself that the Corsican was truly dead. She expected the marble tomb to be grandly sinister and was disappointed. "It looks," she said, "like the bathroom department at Harrods."

Which is all by way of saying how Bonaparte dominated the minds and fears of 19th-century Europe, and has provided 20th-century historical novelists with a mother lode of plots; it's the romance of great events promulgated by a cast of gorgeously costumed rogues. They dazzle us, those amoral Hussars and Lancers, though it is instructive to remember that Jane Austen, writing even as they turned Europe into their private slaughterhouse, blithely ignored them.

But Miss Austen would undoubtedly have approved of the heroine of Polonaise, Jane Aiken Hodge's novel of the Napoleonic era. Jenny Peverel is a most Austenish sort of girl: English, sensible, and with no dangerous good looks to dilute her chances of a dull life. But a dull life is denied our heroine anyway, as she allows herself to be mixed up with hooded members of a Polish secret society, Napoleon's Grande Arme'e, Monsieur Talleyrand, the Czar of Russia, Cossacks and a Virgin Polish Princess who isn't all of those things for long. This is not at all suitable company for a well brought up English girl, and it is only a novelist of Hodge's long experience who could convince us that her adventures might really have happened. There is also a most Austenish hero, Glynde Rendel, who is cleverly maneuvered close to most of the great events in central Europe between 1803 and 1815. It is that tangled web of Polish politics that slows Polonaise to a limp.

There is an American character in Polonaise (I myself introduce American characters solely to increase my sales in the USA, a device I do not recommend as efficacious), who finds central European politics tedious. He's right. More than tedious, inextricably complicated, and Jane Aiken Hodge is too conscientious an historian to allow us to ignore the tangle, with the inevitable result that her characters spend a great deal of time explaining things to each other: "And, as I expect you know, my future husband is a close friend of the Emperor Alexander and of his right hand man, another Pole, Adam Czartoryski" is a fair sampling. Such dialogue denies Polonaise the shock of the familiar -- the sensation that our ancestors were not so very different from us, however odd their manners and conditions now may appear. Indeed, I fear that Hodge is too good an historian, a qualification not altogether desirable in a teller of historical romances who should take care to keep indigestible fact away from the buckling swash and gallivant.

MY GREAT-AUNT Adelaide, returning from Paris fortified in her belief that the French were an aberration of the Almighty, would have appreciated Polonaise as a lengthy read for the boat train. She would have liked Jenny Peverel's determination, she would have approved of Mr. Rendel, and she would have pretended to skip the passion ("It was an earthquake, a heartquake, an explosion.") But no pretence would have been offered for skipping the politics, which Adelaide, just like her great-nephew, would have found every bit as dull as the bathroom department at Harrods.

Bernard Cornwell is the author of the Sharpe novels, detailing the adventures of a British soldier in the Napoleonic wars. His new novel, "Redcoat," a tale of the American Revolution, will be published in the fall.