Word Entry "Hard Rock Returns to Prison from the Hospital for the Criminal Insane"

1. "A screw on the thumb and poisoned him with syphilitic spit." (655).
2. My guess: The word "syphilitic" within this context would probably mean along the lines of acid-like or harmful. I can infer this from the word "poisoned" from earlier on in the sentence.
3. Definition: Pertaining to, noting, or affected with syphilis. (Dictionary.com)
4. Explanation: Knight is trying to enforce the idea that Hard Rock is a man of unstable and dangerous tendencies before he came to the hospital. I also believe the author is trying to illustrate to readers that this is why he was brought to the hospital in the first place.