Myron Magnet is a New Yorker and an architecture buff. In his years editing the Manhattan Institute’s City Journal, he produced the most aesthetically appealing quarterly in America with its black-and-white photographs of elegant New York buildings. But like many New Yorkers he seems not to have gotten around much to the rest of the nation: He only recently visited Mount Vernon and Monticello for the first time. That visit and others have had a happy result, his book The Founders at Home: The Building of America, 1735–1817. It’s a blend of history and architecture, showing how the houses several Founders built (or added onto) reflected their character.

The greatest space is devoted to the most famous Founders—George Washington, Thomas Jefferson, and James Madison. Washington, the second son of a second marriage, lived in Mount Vernon before he finally inherited it. He promptly put his stamp on it, tending even at long distance to the “neatness of my farms” and adding extensions, including a study and, for this “virtuoso of appearance” and “paragon of role playing,” a grand Adam-style New Room, “a stage set for public functions.” This brings to mind Ronald Reagan’s remark that to be president without having been an actor would have been hard.

Monticello was Jefferson’s purposeful creation, built on the top of a hill rather than, like most Virginia mansions, on a riverfront. Magnet sees a “taste for unworldly abstraction” in the house’s empty dome and “the implacable spirit