Then, as now, many Americans held a particular ethnic picture of a terrorist; at that time, it was based on the Italian and Russian radicals credited with bombings over the previous 10 years in Los Angeles, Chicago, New York, Boston, Milwaukee, and Washington. Multiple scenarios for the explosion emerged almost immediately. Attorney General A. Mitchell Palmer thought the Wall Street attack must also be the work of anarchist or Bolshevik groups, and he quickly arrested the head of the Industrial Workers of the World, Big Bill Haywood, “as a precaution.” A less sinister, and less popular, explanation claimed the horse cart belonged to a dynamite company and had simply gone off upon hitting a cobblestone, but by day’s end the fire department had accounted for all such deliveries. “Authorities were agreed that the devastating blast signaled the long-threatened Red outrages,” the Times reported on its front page the day after, while an adjacent article followed the far weirder story of “Two Cards of Warning” sent by the former ninth-ranked men’s tennis player, Edwin Fischer, who had vaguely predicted the explosion to his friends.
Fischer, a seldom-employed 44-year-old sportsman from the Upper West Side, had picked both September 15 and 16 as likely days for the attack; he had also warned a groundskeeper at his tennis club and a stranger on a train and had told a Toronto bellboy that some millionaires were soon to get what they had coming. His brother-in-law, who caught up with him in Ontario after he had mysteriously fled, reported that Fischer had twice been committed to sanitariums but had nevertheless shown psychic powers for several years. Dr. Walter F. Prince, at the American Institute for Scientific Research, told reporters it was possible Fischer had received a “psychic tip” of the bomb plot, like “picking up a wireless message.”
Fischer, it turned out, was not an admirer of Wall Street and predicted bad things happening there pretty regularly. After he was held at Bellevue Hospital, he also told detectives he was an alchemist, a mind-reader, and, least likely, a sparring partner for Jack Dempsey. They pronounced Fischer harmlessly (if annoyingly) insane and released him.
Other explanations for the bombing included a botched robbery or an attack on the Treasury. On the day of the explosion, $900 million in gold bars was being moved out of the Sub-Treasury Building, which was next door to the new Assay Office, where the deadly wagon was parked. At the time it went off, workmen at the Treasury had just closed the side-entrance doors for lunch, possibly saving themselves as well as the gold.
But the answer to this mystery may have been disappointingly plain. Postal workers found circulars mailed a block away between 11:30 and 11:58 on the fatal day: “Remember/We will not tolerate/any longer/Free the political/prisoners or it will be/sure death for all of you/American Anarchist Fighters.”