I do not yet quite know," replied Dr. Silence. "I may first have to make one or two experiments—"
"On me?" gasped Pender, catching his breath.
"Not exactly," the doctor said, with a grave smile, "but with your assistance, perhaps. I shall want to test the conditions of the house—to ascertain, if possible, the character of the forces, of this strange personality that has been haunting you—"
"At present you have no idea exactly who—what—why—" asked the other in a wild flurry of interest, dread and amazement.
"I have a very good idea, but no proof rather," returned the doctor. "The effects of the drug in altering the scale of time and space, and merging the senses have nothing primarily to do with the invasion. They come to any one who is fool enough to take an experimental dose. It is the other features of your case that are unusual. You see, you are now in touch with certain violent emotions, desires, purposes, still active in this house, that were produced in the past by some powerful and evil personality that lived here. How long ago, or why they still persist so forcibly, I cannot positively say. But I should judge that they are merely forces acting automatically with the momentum of their terrific original impetus."
"Not directed by a living being, a conscious will, you mean?"
"Possibly not—but none the less dangerous on that account, and more difficult to deal with. I cannot explain to you in a few minutes the nature of such things,
