David Holmes; Shipbuilder, Craftsman and Inventor

He invented and produced his first binary clock in 1989. The devices measure time with a mechanism that moves back and forth in a simple binary off-on fashion, a system similar to the way computers work. In recent years, Mr. Holmes built several binary clocks set into hexagonal coffee table cabinets. One such device won a "People's Choice" award at the convention of the National Association of Watch and Clock Collectors in Chattanooga, Tenn. It was called "the most inventive clock movement of this century."

"I've . . . enjoyed working with little pieces of wood in intricate ways," Mr. Holmes told the Annapolis Capital in 2007. "Then I became interested in computers and electronics and came up with the thought that clocks make use of all of these parts."

In the 1990s, Mr. Holmes was an electrical engineer, designer and programmer for counting and packing systems and consumer electronics products. He worked for two companies, Batching Systems and DesignTech International.

Shortly after 2000, he left this work to return to the sea. "We sold everything we had and went cruising," his wife said.

For the next several years, they sailed in the coastal waters from Maine to the Caribbean and the Bahamas aboard Adventure. Ashore, Mr. Holmes rented a small workshop on a farm near the Galesville marina and worked on his musical instruments and clocks.

Last year, Mr. Holmes learned he had a walnut-sized tumor, which had metastasized from his lungs into his brain.

In addition to his wife, of Galesville, survivors include two stepchildren, Stewart Andrews of Arlington County and Susan Mower of Pensacola, Fla.; and three grandchildren.