Gilman came from Haverhill, but it was only after he had entered college in Arkham that he began to connect his mathematics with the fantastic legends of elder magic. Something in the air of the hoary town worked obscurely on his imagination. The professors at Miskatonic had urged him to slacken up, and had voluntarily cut down his course at several points. Moreover, they had stopped him from consulting the dubious old books on forbidden secrets that were kept under lock and key in a vault at the university library. But all these precautions came late in the day, so that Gilman had some terrible hints from the dreaded Necronomicon of Abdul Alhazred, the fragmentary Book of Eibon, and the suppressed Unaussprechlicken Kulten of von Junzt to correlate with his abstract formulae on the properties of space and the linkage of dimensions known and unknown.

He knew his room was in the old Witch-House — that, indeed, was why he had taken it. There was much in the Essex County records about Keziah Mason's trial, and what she had admitted under pressure to the Court of Oyer and Terminer had fascinated Gilman beyond all reason. She had told Judge Hathorne of lines and curves that could be made to point out directions leading through the walls of space to other spaces beyond, and had implied that such lines and curves were frequently used at certain midnight meetings in the dark valley of the white stone beyond Meadow Hill and on the unpeopled island in the river. She had spoken also of the Black Man, of her oath, and of her new secret name of Nahab. Then she had drawn those devices on the walls of her cell and vanished.

Gilman believed strange things about Keziah, and had felt a queer thrill on learning that her dwelling was still standing after more than two hundred and thirty-five years.