Patrick O'Brian has spent a quarter of a century constructing a miniature world as detailed and mesmerizing as a ship in a bottle. For 16 volumes most recently The Wine-Dark Sea, a Norton best-seller last fall O'Brian, 80, has charted the 19th-century adventures of British naval officer Jack Aubrey, his best friend and ship's surgeon, Stephen Maturin, and their boat, the HMS Surprise. To date, their little universe has consumed 5,000 pages. Devoted readers who don't know their aft from a hole in the ground are hoping for 5,000 more. Captivated by the Anglo-Irish author's historically rigorous, rousing stories, fans are likely to rip through all 16 volumes in a summer. Then listen to the audiotape editions. Then, perhaps, subscribe to Norton's Patrick O'Brian newsletter, log on to the O'Brian computer bulletin board, and paper their walls with O'Brian calendars and posters. A 17th Aubrey/Maturin novel is in the works as is a movie adaptation of the first book, Master and Commander. Whether the screen can do justice to characters who revel in the pleasure of words will no doubt be a topic of heated computer conversation until the moon rises over the yardarm.