From a distinct writing style for the numeral "1" to a letter "S" that resembles the number 5, three anthrax-tainted letters to Senate Majority Leader Thomas A. Daschle, NBC anchorman Tom Brokaw and the New York Post are providing investigators potentially important clues.
The letters apparently were written by the same person, outside forensic document investigators said. They are characterized by neat block printing and a seeming comfort with writing in English that leave the writer's national origin uncertain, they said.
In addition, the use of the word Allah also stands out, suggesting either a very conservative Islamic writer or someone posing as a Muslim, an Islamic expert said.
Despite the ambiguities, the letters have emerged as a focal point of the investigation into biological attacks. A key goal will be to match the distinctive writing with writing on other documents along the New Jersey postal route from which they apparently were mailed, said Gideon Epstein, former chief forensic document examiner for the U.S. Army and the U.S. Immigration and Naturalization Service.
"It takes time, and it takes resources -- but it's the only physical evidence we have right now," Epstein said in an interview.
The letters to the media are identical, warning both Brokaw and the New York Post editor to "TAKE PENACILIN NOW."
The message to Daschle, D-S.D., was more sinister: "WE HAVE THIS ANTHRAX. YOU DIE NOW."
All were dated "09-11-01," and all concluded with the phrase "ALLAH IS GREAT."
The date is written in American style, with the month preceding the day of the month.
But John Voll, professor of Islamic studies at Georgetown University, did not attach much importance to that, reasoning that anyone who spent time in this country and learned English would have learned U.S. style.
Experts said the text of the letters, which the FBI released Tuesday, left open various possibilities about the sender, ranging from a domestic terrorist to a foreign one, or an American cooperating with foreign terrorists.
The personal, threatening note to Daschle could have been sent by a "bin Laden type" or a "home-grown militant" seeking to capitalize on the Sept. 11 attacks, said Clint Van Zandt, a former FBI psychological profiler.
The letters and the envelopes share distinguishing characteristics pointing to a single writer.
Epstein saw striking similarities between "spacing habits, distance between lines, margins and height ratios between letters."
"It's a three-stroke '1,' " Epstein observed of the number '1' that appears in dates on each of the three letters. "It's an initial stroke into the staff, a vertical stroke and a horizontal stroke on the bottom. That number '1,' whenever it appears in the writing, it's exactly the same way."
Other telltale signs: The "G" looks like a "6," and the "R" is similar to an "A." Foreign writers of English, he said, typically exhibit "more variation with their letter formations."
Investigators are also focused on the content of the letters. Voll said the "stilted" phrasing of the notes, and the use of stereotypical terrorist slogans, might point to a less-educated perpetrator or even a non-Muslim impostor.
Rather than the phrase"ALLAH IS GREAT," most Muslims would be more likely to use the common Arabic phrase "Allahu Akbar," Voll said.
He said a Muslim communicating with a non-Muslim might switch to English usage and say "God is great" or "God is greatest." But only the most theologically conservative Muslims would say "Allah is great," he said.
He said certain phrases in the letters, such as "Death to America" and "Death to Israel," are slogans that might be employed by either "a nonintellectual activist" or a "Hollywood scriptwriter" attempting to sound like a terrorist.