Standing up, I rolled back a corner of the carpet, exposing the floor-planks, and with a brace-and-bit, which I had in my pocket, I bored a round hole in one of these. Into it I screwed the tube, attached to a little watch-like contrivance, twisting the face of the dial so that I could study it from where I proposed to sit. Then I took up my post, smothering a laugh as I noted the expression upon that part of the Major's red face which was visible to me.

Thus began the business of that strange night. Half an hour pa.s.sed in almost complete silence, save for the audible breathing of the Major--by no means an ideal companion for such an investigation. But, having agreed to a.s.sist me, in justice to my old friend I must say that he did his best to stick to the bargain, and to play his part in what obviously he regarded as an insane comedy.

At about the expiration of this thirty minutes, I thought I heard a door open somewhere in the house. Listening intently, and glancing at my companion, I received no confirmation of the idea. Evidently the Major had heard nothing. Again I thought I heard a sound--as of the rustling of silk upon the stair, or in an upper corridor; finally I was almost certain that the floor of the room above (viz. the Major's bedroom) creaked very slightly.

At that I saw my companion glance upward, then across at me, with a question in his eyes. But not desiring to disturb the silence, I merely shook my head.

An hour pa.s.sed. There had been no repet.i.tion of the slight sounds to which I have referred, and the stillness of Low Fennel was really extraordinary. A thermometer, which I had placed upon the table near to my elbow, recorded the fact that the temperature of the room had not abated a fraction of a point since sunset, and, sitting still though I was, I found myself bathed in perspiration. Despite the open door and windows, not a breath of air stirred in the place, but the room was laden with the oppressive perfume of those night-scented flowers which I have mentioned elsewhere, for it was faintly perceptible to me, despite the wet silk.

Once, a bat flew half in at one of the windows, striking its wings upon the gla.s.s, but almost immediately it flew out again. A big moth fluttered around the room, persistently banging its wings against the lamp-shade. But nothing else within or without the house stirred, if I except the occasional restless movements of the Major.

Then all at once--and not gradually as I had antic.i.p.ated--the meter at my feet began to register. Instantly, I looked to the thermometer. It had begun to fall.

I glanced across at Major Dale. He was staring at something which seemed to have attracted his attention in a distant corner of the room.

Glancing away from the meter, the indicator of which was still moving upward, I looked in the same direction. There was much shadow there, but nevertheless I could not doubt that a very faint vapour was forming in that corner ... rising--rising--rising--slowly higher and higher.

It proceeded from some part of the floor concealed by the big saddle-bag chair--the Major's favourite dozing-place (probably from a faulty floor-board), and it was rising visibly, inch upon inch, as I watched, until it touched the ceiling above. Then, like a column of smoke, it spread out, mushroom fashion; it crept in ghostly coils along the cornices, spreading, a dim grey haze, until it obscured a great part of the ceiling.

Again I looked across at the Major. He was staring at the phenomenon with eyes which were gla.s.sy with amazement. I could see that momentarily he expected the vapour to take shape, to form into some ghoulish thing with a contorted face and clutching, outstretched fingers.

But this did not happen. The vapour, which was growing more fine and imperceptible, began to disperse. I glanced from corner to corner of the room, then down to the meter on the floor. The indicator was falling again.

Still I made no move, although I could hear Major Dale fidgeting nervously, but I looked across at him ... and a dreadful change had come over his face.

He was sitting upright upon the couch, the edge of which he clutched with one hand, whilst with the other he combed the air in a gesture evidently meant to attract my attention. He was trying to speak, but only a guttural sound issued from his throat. His staring eyes were set in a glare of stark horror upon the door of the study.

Swiftly I turned--to see the door slowly opening; to see, low down upon the bare floor--for I had removed the carpet from that corner of the room--a ghastly, contorted face, held sideways with one ear almost touching the ground, and with the lower lip and the chin drawn up as though they were of rubber, almost to the tip of the nose!

The eyes glared up balefully into mine, the hair hung a dishevelled ma.s.s about the face, and I had a glimpse of one bare shoulder pressed upon the floor.

Wider and wider opened the door; and further into the room crept the horrible apparition....

The light gleamed equally upon the hideous, contorted face and upon the rounded shoulders and slim, white arms, on one of which a heavy gold Oriental bangle was clasped.

It was a woman!

In a flash of inspiration--at sight of the bangle--my doubts were resolved; _I understood_. Leaning across the table, I extinguished the lamp ... in the same instant that Major Dale, uttering an inarticulate, choking cry, sprang to his feet and toppled forward, senseless, upon the floor!

The study became plunged in darkness, but into the long corridor, beyond the open door, poured the cold illumination of the moon. Framed in the portal, uprose a slim figure, seeming like a black silhouette upon a silvern background, or a wondrous statue in ebony. Elfin, dishevelled locks crowned the head; the pose of the form was as that of a startled dryad or a young Bacchante poised for a joyous leap....

Thus, for an instant, like some exquisite dream of Phidias visualised, the figure stood ... then had fled away down the corridor and was gone!

VI

Close upon a month had elapsed. Major Dale and I sat in my study in London.

"Young Aubrey Wales has gone abroad," I said. "He's ashamed to show up again, I suppose."

"H'm!" growled the Major--"I've got nothing to crow about, myself, by the Lord Harry! There's courage and courage, sir! I've led more than one bayonet attack, but I'd never qualify for the D.S.O. as a ghost-hunter!--never, by Gad!--never!"

He reached out for the decanter; then withdrew his hand. "Doctor's orders," he muttered. "Discipline must be maintained!"

"It was the sudden excitement which precipitated the seizure," I said, glancing at the altered face of my old friend. "I was wrong to expose you to it; but of course I did not know that the doctor had warned you."

"And now," said the Major, sighing loudly as he filled his tumbler with plain soda-water--"what have you to tell me?"

"In the first place--have you definitely decided to leave Low Fennel, for good?"

"Certainly--not a doubt on the point! We're leasing a flat in town here whilst we look around."

"Good! Because I very much doubt if the place could ever be rendered tenable...."

"Then it's really haunted?"

"Undoubtedly."

"By what, Addison? Tell me that!--by what?"

"By a grey vapour."

Major Dale's eyes began to protrude, and:--

"Addison," he said hoa.r.s.ely--"don't joke about it!--don't joke. It was not a grey vapour that strangled Seager...."

"Certainly it was not. Seager was strangled by some wholly inoffensive person--we shall probably never know his ident.i.ty--who had fallen asleep amongst the bushes on the mound, close beside the house...."

"But man alive! I've _seen_ the beastly thing, with my own eyes! You've seen it! Wales saw it! Mrs. Ord saw it!..."

"Mrs. Ord saw her husband."

"Ah! you're coming round to my belief about the Ords!"

"Decidedly I am."

"But what did Wales see--eh? And what did _I_ see!"

"You saw the vapour in operation."

The Major fell back in his chair with an expression upon his face which I cannot hope to describe. Words failed him altogether.

"I had come prepared for something of the sort," I continued rapidly; "for I have investigated several cases of haunting--notably in the Peak district--which have proved to be due to an emanation from the soil--a vapour. But the effect of such vapour, in the other cases, was to induce delusions of sight, in nearly every instance (although, in two, the delusions were of hearing).

"In other words, the person affected by this vapour was drugged, and, during the drugged state, perceived certain visions. I made the mistake, at first, of supposing that Low Fennel came within the same category.

The cla.s.sical a.n.a.logy, of course, is that of the Sibyls, who delivered the oracular responses from the tripod, under the afflatus of a vapour said to arise from the sacred subterranean stream called Ka.s.sotis. The theory is, therefore, by no means a new one!"

Major Dale stared dully, but made no attempt to interrupt me.