Don Foster Has a Way With Words : A LITERARY FORENSICS EXPERT WHO TEACHES ENGLISH AT VASSAR HAS UNCOVERED A SHAKESPEARE ELEGY, CONFIRMED TED KACZYNSKI WROTE THE UNABOMB MANIFESTO AND, WITH THE FBI, IDENTIFIED ERIC RUDOLPH AS A SUSPECT IN THE 1996 ATLANTA OLYMPICS BOMBING.

Closing his evening broadcast on february 15, 1996, poker-faced as ever, CBS anchor Dan Rather intoned, "The same scholar who recently used his computer to identify what he says is an undiscovered poem by Shakespeare and got some high-profile attention for himself has now unleashed his machine on author Anonymous."

Squirming in front of the TV set, Don Foster wondered whether his proverbial 15 minutes of fame might turn into the low point of his career. He had just identified journalist Joe Klein as Anonymous. A mild-mannered professor of literature at Vassar College, in Poughkeepsie, New York, Foster caused a minor academic fuss by arguing that a neglected (and mediocre) 1612 funeral elegy by one "W. S." had actually been written by William Shakespeare. Foster's technique depended less on external evidence of authorship than on an acute analysis of style: word choice, punctuation, spelling, habitual phrasing, poetic devices and the like.

As Rather broadcast that evening more than five years ago, the country was abuzz with gossip about the best-selling roman a clef Primary Colors, based on Clinton's 1992 Presidential campaign. The identity of its author, called simply "Anonymous" on the title page, had been kept a well-guarded secret. Everyone in the capital had a guess who the wasp-tongued insider must be; the Washington Post published a list of 35 suspects. Approached by New York magazine, whose editors had read an article about his Shakespeare attribution, Foster was talked into trying his hand at the puzzle; he had just gone public with his own hypothesis.

Presently, the object of Foster's suspicions, Newsweek columnist Joe Klein, appeared on TV smirking. "Now I know what it's like to be the flavor of the week. It's not me. I didn't do it. This is silly." Foster's humiliation seemed complete. It would take another five months before Klein, under mounting pressure, confessed to the deed. Nearly everyone in Washington had been wrong. Professor Foster had been dead right.

Thanks in no small part to that coup, Don Foster has become a celebrity. Just last winter he made People magazine and newspapers across the country by proving that the beloved American poem, "The Night Before Christmas," had been written not by the straitlaced Bible teacher to whom it had always been attributed, Clement Clarke Moore, but rather by a bon vivant named Henry Livingston.

As the successful results of Foster's technique, which he calls literary forensics, have multiplied, his services have been sought by a whole new set of clients: prosecutors, detectives, public defenders, even the FBI. Four years ago, Foster applied his pyrotechnics to Ted Kaczynski's Unabomb Manifesto. Though he is not at liberty to talk about the case, he was recruited for the JonBenet Ramsey murder investigation in hopes that his analysis of the famous ransom note may yield the identity of the 6-year-old beauty queen's killer. And Foster recently turned to the unsolved Centennial Park bombing at the Atlanta Olympics in 1996 and, with the FBI, helped deduce its likely perpetrator by linking the man to a series of other Atlanta bombings.

Last December, at age 50, Foster published a memoir of his adventures in literary detection, called Author Unknown: On the Trail of Anonymous. It's a lively, personal narrative of what Foster's career in literary forensics has entailed. The book reveals Foster's wry wit, which he turns both on himself, in whimsically self-deprecating passages, and on his opponents. In the mid-1980s, trying to get his dissertation on the Shakespeare elegy published, Foster suffered a series of setbacks at the hands of experts who were asked to peer-review the manuscript. Miffed at their scornful anonymous reports to the publisher, Foster turned his bag of …