Among several fascinating tidbits is the following paragraph in which Hardeen apparently spills the secret of Houdini escape abilities, which I share here with the permission of museum and document owner Roger Dreyer.
Hardeen first explains how Houdini ran away from home at the age of nine, then follows with this bombshell [spelling errors as written]:
While on this trip he became a jockey rode horses and mules &...any thing they put before him. He was accidentally shot in the palm of his left hand, and though at the time it seemed a misfortune--it proved to be the turning point of his life. Because the bullet remaing in the palm of the hand, caused the groth to seem the same as the other hand and apparently was the same. Houdini could contract the hand so that he was able to pull it through the smallest kind of hole. This was the secret that he carried to his grave, and not even his wife knew of it.
No one ever knew about the musclare contraction Houdini was able to perform.
The story of Houdini being shot in the hand is one Houdini himself told, although he set it later in his life. According to Harry, early in his career, he was taken at gunpoint by gamblers and forced to unlock the door of a casino after hours. But Houdini flung the door into the crooks and ducked inside. They took at shot at him through the door, and when Houdini threw up his hand to shield his face, the bullet lodged inside his hand, where it remained for his entire life.
I admit I've never entirely bought the story of the gangsters. Seems like a bit of Houdini fiction. But possibly it was a way to romanticize or misdirect from what Dash claimed was a childhood accident. But I'm still not sure how an object inside Houdini's hand could aid in his escapes. Seems to me it would actually impede his ability to slip out of cuffs, etc.
That brings me to this intriguing footnote in Houdini's Fabulous Magic (page 19) by Walter B. Gibson and Morris N. Young:
Many people thought that Houdini could slip cuffs that were locked about his wrists, but he found that impossible. He even tried compressing the knuckles of his hands in special clamps for hours at a time, hoping to reduce their girth, but it was no avail; so he gave it up.
I've never heard about these clamp compression experiments, but it's likely the source was Walter Gibson, who knew Houdini personally. Was this Houdini once again misdirecting from his big secret? It should be noted that Houdini did slip handcuffs on occasion, sometimes in full view of the audience, and he can be seen slipping cuffs during the jail break sequence in The Grim Game.
Finally, it's worth noting that as he aged, Houdini's left hand gave him problems. He repeatedly broke his wrist, and in 1926 he told a doctor that he only has "50% strength" in his left hand. Could all this be related to the big secret?
While Dash was not above myth-making when it came to his own career (he also claimed to have been once trapped under an ice sheet), he seemed to be the most candid of all the Weisses. He also famously took umbrage to the Harold Kellock biography, Houdini His Life Story, as being "full of lies."
Unfortunately, Hardeen never completed his Houdini biography, so all we have this tantalizing tidbit. But what a remarkable thing to hear from the man who knew all of Houdini's secrets.
Thanks to Roger Dreyer and the Houdini Museum of New York.