This is where things get really strange. Shortly after Cavett's reply, George Hersey, a respected art history professor at Yale, wrote a letter to The Times that ran under the headline "A Secret Lies Hidden in Vassar and Yale Nude 'Posture Photos.' " Sounding an ominous note, Hersey declared that the photos "had nothing to do with posture . . . that is only what we were told."

Hersey went on to say that the pictures were actually made for anthropological research: "The reigning school of the time, presided over by E. A. Hooton of Harvard and W. H. Sheldon" -- who directed an institute for physique studies at Columbia University -- "held that a person's body, measured and analyzed, could tell much about intelligence, temperament, moral worth and probable future achievement. The inspiration came from the founder of social Darwinism, Francis Galton, who proposed such a photo archive for the British population."

And then Hersey evoked the specter of the Third Reich:

"The Nazis compiled similar archives analyzing the photos for racial as well as characterological content (as did Hooton). . . . The Nazis often used American high school yearbook photographs for this purpose. . . . The American investigators planned an archive that could correlate each freshman's bodily configuration ('somatotype') and physiognomy with later life history. That the photos had no value as pornography is a tribute to their resolutely scientific nature."

A truly breathtaking missive. What Hersey seemed to be saying was that entire generations of America's ruling class had been unwitting guinea pigs in a vast eugenic experiment run by scientists with a master-race hidden agenda. My classmate Steve Weisman, the Times editor who first called my attention to the letter, pointed out a fascinating corollary: The letter managed in a stroke to confer on some of the most overprivileged people in the world the one status distinction it seemed they'd forever be denied -- victim.

My first stop in what would turn out to be a prolonged and eventful quest for the truth about the posture photos was Professor Hersey's office in New Haven. A thoughtful, civilized scholar, Hersey did not seem prone to sensationalism. But he showed me a draft chapter from his forthcoming book on the esthetics of racism that went even further than the allegations in his letter to The Times. I was struck by one passage in particular:

"From the outset, the purpose of these 'posture photographs' was eugenic. The data accumulated, says Hooton, will eventually lead on to proposals to 'control and limit the production of inferior and useless organisms.' Some of the latter would be penalized for reproducing . . . or would be sterilized. But the real solution is to be enforced better breeding -- getting those Exeter and Harvard men together with their corresponding Wellesley, Vassar and Radcliffe girls."

In other words, a kind of eugenic dating service, "Studs" for the cultural elite. But my talk with Hersey left key questions unanswered. What was the precise relationship between theorists like Hooton and Sheldon (the man who actually took tens of thousands of those nude posture photos) and the Ivy League and Seven Sisters schools whose student bodies were photographed? Were the schools complicit or were they simply dupes? And finally: What became of the photographs?

As for the last question, Hersey thought there'd be no trouble locating the photographs. He assumed that "they can probably be found with Sheldon's research papers" in one of the several academic institutions with which he had been associated. But most of those institutions said that they had burned whatever photos they'd had. Harley P. Holden, curator of Harvard's archives, said that from the 1880's to the 1940's the university had its own posture-photo program in which some 3,500 pictures of its students were taken. Most were destroyed 15 or 20 years ago "for privacy scruples," Holden said. Nonetheless, quite a few Harvard nudes can be found illustrating Sheldon's book on body types, the "Atlas of Men." Radcliffe took posture photos from 1931 to 1961; the curator there said that most of them had been destroyed (although some might be missing) and that none were taken by Sheldon.