THE MOUNTING EVIDENCE

By DAVID VAN BIEMA

The third typewriter was the lucky one. When federal agents raided the 10-ft. by 12-ft. shack of Unabomber suspect Theodore Kaczynski two weeks ago, they were overjoyed to find two old manual machines, relics of the pre- word processor, pre-Selectric age. Surely, one of these must be the antique on which the bomber pecked out his 35,000 word opus, Industrial Society and Its Future. In straight-faced leaks over the next week, the agents let it be known that, alas, the typefaces did not match, although they had high hopes for a third typewriter, discovered later. What they did not mention was that nestled next to that third machine in Kaczynski's loft was something that made lesser discoveries moot: a manuscript of the manifesto itself.

You may not hear the cheering publicly, since FBI head Louis Freeh is livid that the news was leaked. But do not doubt that hundreds of federal and state investigators, caught up for weeks in the frustrating experience of trying to square the past 18 years of Kaczynski's life with the Unabomber's attacks, are celebrating the discovery of the manifesto amid a mother lode of incriminating evidence. Last Thursday, when the Justice Department named New Jersey First Assistant U.S. Attorney Robert J. Cleary to lead the team that will prosecute Kaczynski, the hot speculation was over whether the initial prosecution would take place in Cleary's state, where the Unabomber murdered advertising executive Thomas Mosser in 1994, or in California, where timber lobbyist Gilbert Murray was killed in 1995. Prosecutors could seek the death penalty in either case.

Up until the search of Kaczynski's cabin, federal authorities were not totally sure that the Lincoln hermit was their man. No one had ever seen Kaczynski mail a bomb. Several clues the Unabom task force has long held in hand are not foolproof. The few fingerprints recovered from the Unabomber's efforts, say investigators, are missing the central whorls; even if Kaczynski's matched, a jury might not be persuaded. Unknown to many, the bombs had yielded bits of hair and fiber, but the cops could not be sure they were the perpetrator's. Nor were they sure they had collected enough DNA from the bomber's stamps and parcels to match the suspect's saliva.

Hence their satisfaction about what turned up in the cabin, even before the manuscript surfaced. In addition to the bombmaking notes and paraphernalia and the half-made bomb they found immediately, agents soon encountered a finished product: they had to delay the search while they defused it. Its structural peculiarities, experts said, were exactly those of the Unabomber bombs. The searchers also discovered a piece of paper with the words "hit list" written above "airline industry," "computer industry" and "geneticists." Evidence from the cabin was so strong, federal officials said, that it might convict Kaczynski without having to match his whereabouts with the bomber's at the time of the crimes.

And that had begun to seem a good thing. Government investigators believe Kaczynski took buses from Lincoln to Helena to Butte, Montana, where he could have connected to Salt Lake City, Utah--the origin of several of the bomber's 1980s strikes--or to Sacramento, California, and the San Francisco Bay Area, from which four 1990s bombs were sent. But pinpointing his presence in those destinations was tougher. Despite his family's statements that Kaczynski lived in Salt Lake City in the early 1970s, checks with motels and blood banks have failed to turn up any record of him there a decade later.

In Sacramento several employees at a Tower Books store 20 blocks from the bus station took one look at a newsmagazine cover last Monday and yelled, "Hey, this is Einstein!" That was their name for a wild-haired, ripe-smelling man who, for a few years until 1994, had shown up regularly in the spring and browsed through science books without buying. But a hotel clerk who told the press that Kaczynski had boarded at his establishment at the same times was less sure of himself when talking to investigators. A federal agent in California was heard to sigh, "I sure wouldn't want to prosecute him yet."

The manuscript's discovery will make prosecution a much surer bet. Initial tests have indicated it was typed on the typewriter next to it; and the FBI had previously determined by examining the manifesto sent to the papers, the Unabomber's missives to various newspapers and a gloating note to one victim that all three emerged from the same machine. In fact, lying next to the treatise in the cabin was a version of one of the bomber's letters to the New York Times. As America's trial watchers are aware, there is no such thing as a sure thing. But the federal agents in Montana, at least, are convinced that the proof is in and the hermit of Lincoln and the Unabomber are one and the same.

--Reported by Jordan Bonfante/Sacramento, Elaine Lafferty/Salt Lake City and Elaine Shannon/Washington

With reporting by JORDAN BONFANTE/SACRAMENTO, ELAINE LAFFERTY/ SALT LAKE CITY AND ELAINE SHANNON/WASHINGTON