On the morning of October 30, 1928, a worker at the police station of Lake Bluff, Illinois went into the basement to light the furnace. He found a naked woman propped up against the furnace, covered in deep, gruesome burns. She was Elfrieda Knaak, a twenty-nine year old book salesperson and Sunday School teacher.

In the hospital, she insisted “It was all my fault,” and “I did it myself.” Her sense of “faith,” and “purity and love,” inspired her to thrust her arms and legs into the flames to “prove her faith in the spiritual” and make herself worthy of her “astral sweetheart.” She wanted to “commit myself right in the eyes of God.” It was, in short, one of the worst purification rites on record. She said that as she began to feed herself to the flames, she heard voices, and saw hands beckoning to her from inside the fire, which gave her the will to go on with her deed. When asked how she had been able to unlock the door leading to the furnace room, and then lock it from the outside, she replied it was “A mystic hand.” However, just before her death, she suddenly admitted that there had been someone else in the furnace room with her. She had made a suicide pact with another woman, who had instead run away after Knaak had been burned. She then changed her story yet again, stating that “Frank threw me down,” and “They did this.” She told her brother Alvin yet another version of the tragedy, saying “I made a mistake. It was I alone that did it. I went alone.” She disclosed that someone had given her the key to the furnace room, but she did not say who that might have been. She tried to say the name of a woman who would, she said, “explain all,” but unfortunately, she died before she could make the name intelligible to her questioners.

The coroner’s jury shrugged and ruled her death as suicide. The police, however, were much less ready to dismiss the possibility of foul play. They reasoned that the door of the furnace was too high and too small for her to have burned her own legs and feet so severely. Also, a bloody handprint was found on the door, along with blood-soaked footprints leading up the furnace room stairs and back. And, of course, there was that locked door. Adding to the mystery is the fact that the autopsy found that the dead woman had not only been burned, but struck over the head and electrocuted.

Found in Knaak’s purse was a letter she had received from a new-found friend, a woman who signed her name “B. E. Lock.” Evidently, they had a shared interest in what was described as “religious discussion.” It soon transpired that Knaak’s interest in religion had taken some unorthodox turns. She followed the “New Thought” movement, a somewhat amorphous "mind-cure" belief system with links to Theosophy and Christian Science. It preached the importance of astral projection and “spiritual purification.” It suggests that either Knaak or someone close to her took the concept of “purification by fire” many, many steps too far. ("B.E. Lock" was later discovered to be a Luella Roeh. She told police that Knaak had a fascination amounting "almost to hypnotism" for her, but was unable--or unwilling--to give any details that might have explained the young woman's death.)

On the day of the burning, Knaak had journeyed to Chicago on a business meeting. She left work and, around six in the evening, was seen at the Highland Park depot. She made two phone calls: one unanswered, and one where she spoke in guarded whispers. She bought a round-trip ticket to Lake Bluff and was seen arriving there later that night. This is the last known sighting of her until she was found in the City Hall. Knaak had been involved with a married actor/policeman/elocution teacher named Charles W. Hitchcock, with whom—so she said—she shared a “pure,” “astral” love. She told her doctor that “Hitchy got me out of hell about three months ago,” but gave no further details. Before her death, she told investigators that she had gone to Lake Bluff that night in order to see him.

Hitchcock, on the other hand, insisted to authorities that he had not been romantically involved with the dead woman. This has an “Of course, he’d say that,” ring to it, except that at the time of Knaak’s death, he had a badly broken leg which left him house-bound. Unless Mrs. Hitchcock was a remarkably tolerant sort, it seems unlikely that he’d have any lovers, astral or not, dropping over for a visit.

A month after Knaak’s death, a Texas man who described himself as a “student of occult mysticism” wrote to the police declaring that he had helped her burn herself to death. He claimed that she had asked him to place her into the furnace. The man was quickly ruled insane and sent to an asylum, but he doesn’t seem any crazier than anything else about this story.

So, which of Knaak’s deathbed confessions was the truth? Was it murder, suicide, or some bizarre combination of the two? Or were all her statements the product of a dying woman’s delirium, inspired by the heavy doses of narcotics she received in the hospital? The only “Frank” who had any known link with Knaak was a violin teacher named Frank P. Mandy, who shared a studio with Charles Hitchcock. However, it was uncertain that he and Knaak had ever even met, and he does not seem to have been regarded with any real suspicion.

Knaak’s death remains as creepily mysterious now as it was on that curiously-close-to-Halloween day in 1928.

[Footnote: Illinois saw an odd epilogue to this case. Several months after Knaak’s death, a young Evanston woman named Helen Friedrich tried to kill herself by shoving herself into the family home furnace. Although she severely burned herself, she later sobbed that she had been “too much of a coward” to go through with it. Also cf. the equally disturbing furnace death of Addie Sheatsley four years earlier.]

Elfrieda Grace Knaak