He put the tips of his fingers together and surveyed us with the benign condescension of one instructing a class of small children.
"The first night that you passed in your newly purchased house, Roger, you accidentally encountered Miss Michell; or she did you!" He smiled humorously. "While your feelings were excited by the unusual episode, the strange surroundings and the dark, she related to you a wild legend of witchcraft and monsters. Later, when you suffered your first attack of marsh-gas poisoning, your consequent hallucination took form from the story you had just heard. Later conversations with your mysterious lady fixed the idea into an obsession. Recurrent dreams are a common phenomenon even in healthy persons. In this case, no doubt the exact repetition of the physical sensations of miasmic poisoning tended to reproduce in your mind the same sequence of ideas or semi-delirious imaginings. These were of course varied or distorted somewhat on each occasion, influenced by what you had been hearing or reading in advance of them. This mental condition became more and more confirmed as you steeped yourself more deeply in legendary lore and also—pardon me—in the morbid fancies of the young lady; whose ghostly visits in the dark and whose increasing interest for you put a further bias upon your thoughts."
"What were the noises I heard from the lake, and the shocks we all felt?" I demanded.
He nodded amiably toward Vere.
"Mr. Vere has mentioned the large bubbles which formed and burst on the surface of the lake. That is a common manifestation of ordinary marsh gas. Possibly the singular and unknown emanation that took place at night came to the surface in the form of a bubble or bubbles huge enough to produce in bursting the smacking sound of which you speak. But I am inclined to another theory, after a walk I took about your place this morning. When you put up your cement dam instead of the old log affair that held back only a part of the stream, you made a greater depth and bulk of water in the swamp basin than it has contained these many years, if ever. As a result, I believe the sloping mud basin began to slip toward the dam. Oh, very gradually! Probably not stirring for weeks at a time. Just a yielding here, a parting there, until the cloudburst precipitated the disaster. You had, my dear Roger, a miniature landslide, which would account for sounds of shifting mud and water in your lake, and for the shocks or trembling of your house when the earth movements occurred."
The rest of us regarded one another. I think Vere might have spoken, if he had not been unwilling to mar Phillida's contentment by any appearance of dispute with her father.
"It is very cleverly worked out, sir," I conceded. "But how do you explain that Desire knew what I experienced with the Thing from the Barrier, if my experiences were merely delirious dreams?"
"I have not yet understood that she did know," said the Professor dryly. "She put the suggestions into your head; innocently, of course. When you afterward compared notes and found they agreed, you cried 'miraculous'! How is that, Miss Michell? Did you actually know what Roger experienced in these excursions before he told you of them?"
Desire gazed at him with her meditative eyes, so darkly lovely, yet never quite to lose their individual difference from any other lovely eyes I have ever seen. The eyes, I thought then and still think, of one who has seen more, or at least seen into farther spaces, than most of treadmill-trotting humanity. She wore one of the new frocks for which Phillida and she had already made a flying trip to town; a most sophisticated frock from Fifth Avenue, with frivolous French shoes to correspond. Her hair of a Lorelei was demurely coiled and wound about her little head. Yet some indescribable atmosphere closed her delicately around, an impalpable wall between her and the commonplace. Even the desiccated, material Professor was aware of this influence and took off his spectacles uneasily, wiped them and put them on again to contemplate her.
"I am not sure," she answered him with careful candor. "I believe that I could always tell when the Dark One had been with him. I could feel that, here," she touched her breast. "I knew what its visits were like, because I was brought up to know by my father and was told the history of the three Desire Michells. My father had studied deeply and taught me—I shall not tell anyone all he taught me! I do not want to think of those things. Some of them I have told to Roger. Some of them are quite harmless and pleasant, like the secret formula for making the Rose of Jerusalem perfume; which has virtues not common, as Roger can say who has felt it revive him from faintness. But there are places into which we should not thrust ourselves. It is like—like suicide. One's mind must be perverted before certain things can be done. And that is the true sin—to debase one's soul. All men discover and learn of science and the universe by honest duty and effort is good, is lofty and leads up. Nothing is forbidden to us. But if we turn aside to the low door which only opens to crime and evil purpose, we step outside. I am unskilful; I do not express myself well."