On Friday night Feb. 15 at a Florida resort hotel, Julian H. Singman, a prominent Washington lawyer-lobbyist, told a business associate that he was meeting a man for dinner to discuss Singman's interest in selling his 56-foot $300,000 yacht, the Calpurnia.

Seventeen days later, a fisherman nearly 500 miles away spotted Singman's bullet-riddled body in a muddy coastal creek near Savannah, Ga. Yesterday, Georgia police charged a 36-year-old North Carolina man, who was wanted on bad check and larceny charges, in the slaying of Singman, 56, president of the Maritime Institute for Research and Industrial Development.

Details of the death of Singman, whose Washington career spanned two decades in influential positions in government, industry and labor union circles, remain a mystery to Florida, Georgia and FBI officials investigating Singman's disappearance from an AFL-CIO gathering he attended last month in Bal Harbour, Fla.

"We have difficulties in this case accounting for Mr. Singman's time, his movements . . . and the motive," said Police Chief Al St. Lawrence of Chatham County, Ga. "There is an eight or nine day gap, where nobody we know of had seen him."

Singman was shot four times in the torso with a .38-caliber revolver, and his body had been in the water roughly three to five days, but authorities are unsure when and where the killing took place, according to Joseph Del Campo, an FBI spokesman in Miami.

The victim and the suspect, Furman Clark Jr., who is now in custody, had been referred to each other by a yacht broker, according to C. James Patti, vice president of the maritime association, who said Singman had told associates he was planning to meet Clark to discuss the Calpurnia. The maritime association supplied Clark's name to police after the disappearance.

Following Singman's disappearance, the FBI broadcast a description of Clark's 1983 truck, which was spotted Monday near Savannah, police said. Authorities said they obtained a search warrant for Clark's vehicle and recovered a .38 caliber Smith & Wesson revolver that ballistics tests showed was the murder weapon.

Local, state, and federal authorities in three states are now investigating the unexplained movements of two very dissimilar men who shared an interest in boats -- a wealthy Washington executive and a North Carolinian facing criminal charges in three states -- to determine what happened since Singman left the Sea View Hotel near Miami Beach with thoughts of selling his trawler.

Singman's belongings were still in his hotel room and his rented gray Chevrolet was still in the hotel parking lot when he disappeared. He planned to return for week-long AFL-CIO meetings involving maritime unions, with which Singman's industry negotiates.

Clark is wanted on bad check warrants in North Carolina, Georgia and Virginia, including a case in which he is accused of writing a $2,500 check to purchase a truck, authorities said.

Singman, a bachelor and avid yachtsman who lived aboard the Calpurnia at the Capital Yacht Club on the Southwest Washington waterfront, was well known and respected here in boating circles and on Capitol Hill, associates said. A Washington native, he graduated from George Washington University and Harvard Law School, and had been deputy administrator of the U.S. Maritime Administration, associate chief counsel for the House antitrust subcommittee, and a former union lawyer.

"He was a very thoughtful, extremely intelligent, and capable man. And a careful thinker," said James Hamill, the rear commodore of the yacht club, where Singman served on the board of directors. "He was quiet, and somewhat to himself, but very well liked . . . . It is hard to believe that kind of thing happens to someone so active, so respected . . . . "

"An extremely charming, personable, friendly man, and a pleasure to work for," Patti said of his boss. "A guy you could have a drink with and talk about the Redskins with."

Henry Singman, the victim's brother, said Singman had been in very good spirits lately. "He had been very up for the trip . . . and for selling the boat. He said the boat was too big."