When Mike Humphries launched the St. Clement's Island-Potomac River Museum as its director in 1975, he and two part-time employees welcomed about 2,000 visitors a year to a small building at Colton's Point.

Now, Humphries, 63, is retiring from an institution that last year saw more than 20,000 visitors coming to four different locations: an enlarged complex at Colton's Point; the Piney Point Lighthouse; the Drayden African American schoolhouse; and the Black Panther, a World War II German sub sitting at the bottom of the Potomac and known as the state's first "shipwreck dive preserve."

"We've come a long way from a two-room riverfront house," said Humphries, who is leaving to become museum director for the city of Montgomery, Ala.

As the St. Clement's Island-Potomac River Museum has grown, the land and the livelihoods it commemorates have changed, losing some of what the institution seeks to preserve, at least under glass. Tobacco is a waning crop, and the number of workboats plying the Potomac and its tributaries has plummeted.

"When I first came, you could almost walk across the oyster boats, now you're hard-pressed to see three or two, the same with crab boats," he said. "But we do have eagles and pelicans."

Humphries, a native Washingtonian, graduated from the University of Maryland and earned a master's degree in museum studies from George Washington University. "Before that, I was in the Marine Corps, University of Parris Island, 1958. My God, I don't even want to go there. That was a long time ago."

He was teaching high school American history in 1974 when he helped to plan the new museum, which was originally a project of the Seventh District Optimists. In 1976, he became its half-time paid director, and eventually it turned into a full-time job.

The museum was briefly under county auspices, operated on its own from 1978 to 1982, then returned to the county fold -- under the Department of Recreation and Parks -- in 1984 for the 350th anniversary of the founding of the Maryland colony.

Humphries vividly remembers the event, marked by so much drenching rain that wags were calling the site of the landing in 1634 "Inclement Island." The event also coincided with the dedication of a new museum building at Colton's Point.

"The day before, it was in the seventies and beautiful, and the Lord High Chancellor from London and [State Comptroller] Louis Goldstein were there," Humphries said. "The next day, I was lying in bed, and I thought I heard guns from Dahlgren. It was thunder."

The museum's primary focus at Colton's Point is on the landing at nearby St. Clement's Island of the ships Ark and Dove. The British colonists came under a royal charter granted in 1632 to Lord Baltimore, and, led by Father Andrew White, they celebrated the first Catholic Mass in English-speaking America.

"The genesis of Maryland begins with Henry VIII, because that's when the Catholics were out," Humphries explained. "Maryland was supposed to be a Catholic colony, which it was not. Most were Protestants. They landed on St. Clement's Island to provide me with a job."

Soon after landing, he noted, the colonists chose to build their settlement at St. Mary's City because it had a better harbor and was closer to the bay and farther from potentially hostile natives.

Because the settlers quickly moved on, Humphries said the St. Clement's-Colton's Point area "ends up the poor sister to more recognized sites. We're the third English settlement in the New World that was successful."

However, history records that Kent Island was settled three years earlier by William Claiborne, a trader from Virginia, making St. Mary's County the fourth settlement.

Humphries acknowledged such "awkward" details but said, "William Claiborne was part of Virginia. He was in the wrong place at the wrong time. . . . The first English settlement in Maryland was definitely Kent Island. You're right. It just wasn't Maryland. It was Virginia. But then [before the contested grant to Lord Baltimore] all of Maryland was Virginia, wasn't it?"

During his watch, the one-room Charlotte Hall School built in 1820 was moved to the museum grounds, which spread over 24 acres, another house was purchased for a gift shop and a new parking lot was added. On weekends from Memorial Day until the Blessing of the Fleet in October, the museum runs a tour boat to St. Clement's Island.

Humphries boasts that his museum has more registered historic sites than any other in Maryland except for Historic Annapolis, which has five, and soon they could be tied.

"We're also creating a new Potomac River Maritime Museum, at the old Steuart Transportation offices adjacent to the lighthouse," he said. The waterfront site, which the county bought, includes three buildings.

Under Humphries, the museum received national accreditation, in 1992, and an award for excellence from the Maryland Historical Trust, in 2000. It has five full-time employees and six part-time seasonal workers. It is open seven days a week from March 25 through Sept. 30 and Wednesday through Sunday the rest of the year.

So after nearly three decades, Humphries said, it's time for him to depart. He has put his Breton Bay townhouse on the market for $205,000 but says, "We'll take less." Then he mused, "I wonder how long I'll last down there. I might get homesick."

Mike Humphries guided the growth of St. Clement's Island-Potomac River Museum for 28 years. He's leaving for another museum job, but he wonders "how long I'll last. I might get homesick."