Forrest L. Cromwell, 83, a master watchmaker who trained a number of local jewelers and did complicated repairs for the Smithsonian Institution and other clients, died Dec. 27 at Doctors Community Hospital of complications from a perforated ulcer.

Mr. Cromwell, a longtime resident of Washington's Dupont Circle neighborhood, moved to Arlington four years ago.

In addition to his reputation as a watch and clock expert who could make parts for antique timepieces, Mr. Cromwell was known as a man of many talents and as something of a character. At various times, he had been an artist, photographer, mapmaker for the Army, charter boat captain on the Chesapeake Bay and crabber.

The close study of fish behavior was a lifelong passion. In fishing circles, he was considered the unofficial carp fly-fishing champion of the lower C&O Canal. For many years, he was a National Park Service volunteer along the canal, where he first began fishing as a youth and later piloted canal boats.

Writers for The Washington Post and other publications interviewed Mr. Cromwell from time to time about his fishing techniques, the vast collection of interesting and not-so-interesting objects stuffed into his Dupont Circle town house, and the state of development in that Northwest neighborhood.

Post sports writer Dennis Collins said in a 1982 article that he was "as much a fixture on the canal as the old locks." Mr. Cromwell was credited with inventing the mulberry fly sold by a fishing equipment shop near the canal.

In a 1978 Post profile titled "The Collector," Henry Allen wrote of visiting the town house, a kind of museum of Mr. Cromwell's many interests:

"You don't know what kit and caboodle means 'til you have to edge sideways down the hall past Forrest's living room, where he claims there's furniture buried under: cans of motor oil and Rustoleum, a softball, a stepladder, a number of felt hats, his father's salmon rod, a copy of 'Everest: The Western Ridge,' an old tire, raincoats, piles of newspapers, a piece of plaster ceiling dangling from the laths, a stuffed Winnie-the-Pooh, a pair of ancient sneakers with the counters busted down flat, a pot crammed with umbrellas, canes, galoshes and a grease gun, fishing line hanging off the lamps, a pair of black gloves, a pamphlet open to an article entitled 'Coping With Oranges,' several empty spring-water bottles, more fishing rods, an aquarium, a copy of 'Henry Moore' and Forrest's painting of the old C&O canal lock house he and his mother used to visit."

"I've been a collector since the day I was born," Mr. Cromwell told Allen. "It's a disease. It's in your genes. Terrible disease. Keep everything. I like everything old, nothing new. I have about six TVs in the house, only two work. I keep the other four in case I need a diode or a tube."

Mr. Cromwell's interest in fishing began in childhood, on the banks of trout streams near his native Boothbay Harbor, Maine.

His mother, who had been widowed during World War I, moved to Washington when he was 9.

After attending Central High School, he studied at the Corcoran School of Art.

He worked for the War Department during World War II as an expert in chronometers.

He was a charter boat captain in the late 1940s and drew maps for the Army Map Service during the 1950s. He ran his watch repair business out of his home until retiring in the mid-1990s.

Mr. Cromwell's first marriage, to Mary Parsons, ended in divorce. His second wife, Laura Bayliss, died in 1951, and his third wife, Helen Selvig, died in 1994.

There are no immediate survivors.