It's nothing but sheer luck that George Washington wasn't named George Heartburn. And that we would all be living in Heartburn, D.C.

George got a birthday card today, drawn and personally delivered by 15-year-old Gary Robertson of Washington-on-Tyne-and-Wear in northern England. He is to spend a few days here with his parents, Mr. and Mrs. Ray Robertson, and David Warden of the Washington Development Corp.

"It's a bit of a promotion, actually," Warden said diffidently as the family gawked their way through the Air and Space Museum yesterday. Today Robertson, the winner of a birthday-card contest, sponsored by the British-based corporation, was to have lunch at the White House, visit the mayor and see some sights, and Wednesday, just before returning home, they will drive to Mount Vernon.

The English Washington is one of those mined-out coal towns near Newcastle that is pulling itself back up via the "new town" movement, not to be confused with the suburban London planning experiments called new towns. So far, 18 villages have been created from scratch around Washington, bringing the population to 55,000 and luring new industry, such as the Northeast Computer Supplies for which the senior Robertson works.

But why Washington? In England?

"This is one of those cases where the family took its name from the area, not vice versa," Warden said. "In Anglo-Saxon days it was called, we think, something like Wessas Son's Farm. In 1183 a man named William the Hertburn moved there and took the name William de Wessyngton. Now, if he hadn't done that, it probably would be Heartburn today."

William's family crest, which was also George Washington's personal crest, by the way, featured three stars and two bars--today the flag of the District of Columbia and very likely the inspiration for the Stars and Stripes.

The development corporation plans to bring the winner of a student essay contest here in July for a week, and in April its top officials will fly over to plant a ceremonial tree at Mount Vernon.

Gary Robertson, a fourth-form high school student, wants to take up art or graphics as a career. His winning card has an eagle, flanked by maps of Britain and the United States, scenes from his hometown and some American landmarks such as the Statue of Liberty.

"I think we pay more attention to George Washington in the U.K.," he said. He hasn't made a special study of the man, however.

The Robertsons, slightly dazed by the bustle of the crowded museum, were looking for a lunch counter. They have already discovered hamburgers. There are two younger brothers at home with a grandfather.

And what was it Gary wanted to see most of all here?

"I should have liked to go to Disney World," he said, just a shade wistfully.