The road from Washington to Monticello winds deep into American history across the Virginia foothills. Monticello was the mountaintop home of the most revered of the founding fathers and the third US president, Thomas Jefferson.
But the day we took that road, the bus was full of chat about the new Jefferson scandal, not about his authorship of the Declaration of Independence back in 1776 which he called "an expression of the American mind".
It has long been a blot on Jefferson's towering reputation that the man who wrote that "all men are created equal" and have a right to "life, liberty and the pursuit of happiness" kept 135 slaves on his plantation at Monticello. But now the country is abuzz with the story of Jefferson sleeping with a slave called Sally Hemings and having at least one child by her.
Is this not more evidence of the hypocrisy of this Renaissance man who could read seven languages?
Had he not written in his only book, Notes on the State of Vir- ginia, that blacks have a "very strong and disagreeable odour" and that for whites to breed with them "produces a degradation . . . to which no one can innocently consent"?
The guide at Monticello said she assumed we had all read about the claim in Nature magazine that there was now DNA proof that Jefferson had fathered a child by Sally Hemings.
Up to now this had been mere rumour going back to a journalist, James T. Callender, who wrote in 1802 that Jefferson had kept "a concubine" called Sally and that her eldest son, Tom, bore a striking resemblance to the then president.
Historians had dismissed this as character assassination. Descendants of Sally Hemings, who had always claimed kinship with Jefferson based on family oral tradition, were also dismissed by the legitimate descendants grouped in the Monticello Association who alone have rights to be buried in the cemetery near the patriarch.
Now Sally Hemings's presence floated around Monticello's graceful rooms, well removed from the slave quarters called Mulberry Row. As the visitors viewed the Jefferson bed, built into the wall between his study and bedroom, one wondered whether this was where the lonely widower sought consolation from a woman he literally owned.
Many Virginia slave-owners did sleep with their slaves, and elaborate rules had developed for deciding when the offspring of such unions were classified as mulatto rather than black.
Sally herself was mulatto and was actually the half-sister of Jefferson's wife, Martha. Sally was the offspring of a liaison Martha's father had had with one of his slaves.
Sally was a "quadroon", meaning she was of one-quarter negro blood. According to Jefferson's theory, any child she had by a white man would cross the colour line and "clear the blood". Some commentators now wonder if Jefferson justified his liaison with Sally in this way. Her son, Easton, of whom Jefferson was almost certainly the father, later became officially white and respectably middle-class while his two brothers, Thomas and Madison, stayed in the black community.
The reactions to these revelations have varied enormously. As the news of the DNA tests came just a few days before the midterm elections, some wondered if this was just a coincidence. If the great Jefferson had his dalliance with a slave girl, did this not put the dalliance with a White House intern by William Jefferson Clinton into proper perspective?
For some, the liaison was yet another example of sexual exploitation of the master-slave relationship. But others speculated that Jefferson had really fallen in love with Sally after his wife's early death and that the relationship had lasted the 30 years until his own death.
The African-American historian, Annette Gordon Reed, had argued in a book published last year before the DNA experiment that Jefferson had at least one child by Hemings. She was dismissed by other historians who have now to eat their words.
She sees the relationship as much more complex than sexual exploitation.
She and other black commentators wonder if it will not help to show modern America that race is not (pardon the pun) a simple black and white issue as it is often presented.
The new findings will make Jefferson "more human", she says. "We're not two separate people, blacks and whites. We're related by culture and by blood." The nuances of that relationship need to be understood. "Slavery was not monolithic. And it demeans the lives of individual slaves not to give justice to those nuances," she told the Washington Post.
The Monticello Association, grouping 800 of Jefferson's legitimate descendants, are not all happy with the nuances, however. They jealously guard the Jefferson cemetery for their own use.
Now one of them, Lucian Truscott, has invited all of Sally Hemings's descendants to attend the next annual meeting of the association.
He expects resignations from some of the "crusty old-time Southerners who have threatened to quit if one member of the Hemings family is allowed in". It will be sad if the cemetery a few hundred yards from the neoclassical Monticello, designed and built by Jefferson, becomes a racial battleground.