Chapter XXIII

_The End of the Coil_

Warriner laid the book on the table, and pulled out his pipe. I think it was a full five minutes before any of us said a word. But Betty kept her hand close-locked in mine.

"Any particular questions?" said Warriner at length.

"If I've got the hang of it," I began, "the Sigma ray was bound to get the man or woman who happened to be sitting in that big chair on the specified dates in June when the sun was in position to shine through the bullseye lens."

"Yes."

"Then I escaped through the accident that, when the window was repaired, the lens got mixed up with the ordinary gla.s.s bullseyes."

"Precisely. It had been replaced in a new position, an entirely unknown one. As it happened--pure chance, you understand--the ray of sunshine that fell upon your face at noon that day had pa.s.sed through a bullseye of common purple gla.s.s, and therefore it was harmless. But the Terror was in the room; somewhere it was lying in wait, ready to strike. Do you recall how I kept close to the wall, so as to avoid getting in the path of the direct sunlight? You understand now that I realized the danger, and took the obvious precaution. But John Thaneford was unaware that any change had been made in the position of the death-dealing lens. And so he walked straight into the line of destructive force; and the Sigma ray, being no respecter of persons, proceeded to strike him down."

"I wonder how much he really knew about the whole affair?" queried Betty. "You remember that Eunice expressly acquitted John Thaneford of any actual part in my father's death."

"But he certainly must have been cognizant of the nature of the trap,"

answered Warriner. "He was the observer at the time of Mr. Graeme's death, the elder Thaneford being physically unable to take his accustomed post on Sugar Loaf. Again, his putting Hugh, bound and helpless, into the fatal chair is unanswerable evidence that he did possess a guilty knowledge of his father's secret. It makes no moral difference that he had no hand in inventing or setting up the instrument of vengeance. He knew of its existence undoubtedly, and hoped to profit by it. That's enough."

"Have you any theory about the Sigma ray itself?" I asked. "Or rather its effect upon the physical organism?"

"Do you happen to recall the medical testimony given at the coroner's inquest by Doctor Williams of John Hopkins? Well, he testified, in brief, that the autopsy had revealed a most peculiar lesion of the brain; in unprofessional language, the injury might be characterized as a case of greatly intensified sunstroke."

"Yes, I do remember."

"Now there are unexplained anomalies about even ordinary sunstroke,"

continued Warriner. "Just what are the conditions under which exposures to the rays of the sun may be dangerous?

"In the first place, we may affirm confidently that the peril is not dependent upon the amount of humidity that may be present in the atmosphere. Down in New Orleans, where the air is full of moisture and the thermometer stands high in the scale for weeks at a time, sunstroke is virtually unknown; men and beasts seem equally immune. But let a ten-day heat wave submerge New York City and the emergency hospitals will be full up, while the horses will be wearing plaited straw-bonnets as a protection against the deadly sun.

"Again, there is Fort Yuma in Arizona, the hottest place in the United States, with the possible exception of Death Valley. Yes, it is abnormally hot at Yuma and the air is furnace-dried; the old-timers will tell you that, on really bad days, a man can't drink water fast enough to keep from dying of thirst. Of course, men do die from the effects of the heat, but it isn't our ordinary form of sunstroke. To sum up, then:

"No sunstroke at New Orleans, where it is abnormally humid and hot; and none at Fort Yuma, where it is abnormally dry and hot. But plenty of cases in Paris, Chicago, and New York, where the climate is supposed to be temperate.

"The inference is logical: under certain conditions, one of the invisible, high frequency rays, always present in sunlight, is enabled to get in its deadly work. Unfortunately, we don't know what those conditions are. Perhaps the proportion of static electricity in the atmosphere may have something to do with it. Anyway, the fact remains that men do die of heat stroke in New York and Paris, while Louisiana and Florida are comparatively free from that particular peril to life."

"Then, according to your theory, it is the Sigma ray which is the active lethal agent in sunlight?"

"Yes, and Fielding Thaneford's invention enabled him to isolate the ray in question, at the same time enormously intensifying its action. Both Graeme and John Thaneford died the instant that it touched them."

"And that was Fielding Thaneford's secret," said Betty, just returned from a flying visit to the nursery, where Little Hugh lay sleeping.

"Such a horrible secret!" She shuddered.

"Just as well that it died with him," a.s.sented Warriner soberly.

"Still, in the end, he sought to stop the evil thing that he had set in motion," persisted Betty. "He told me all he could; all indeed that it was necessary to know, once I really began to use my wits."

"Which reminds me," I put in, "that you have yet to explain how you finally managed to read the cypher. What put you back on the track?"

"So simple a thing it was, too," laughed Betty. "And so easy to overlook."

"I remember years ago," remarked Warriner, "that, on account of certain rare astronomical conditions, it was possible to see the planet Venus at midday. It took me the longest time to find the star, although I thought I knew just where to look; also all my friends were admiring the spectacle. At last I saw it, and then it was an easy matter to locate it again. I suppose the reason is that I didn't know what to expect; some sort of junior sun, I reckon. In reality, it was only a pin-point of light, but brilliant as a diamond."

"And there's the game of challenging an opponent to find a word in a geographical map," said Betty. "It isn't the one printed in fine type and tucked away in a corner that is so hard to discover. The really invisible word is the one stretching in big, widely separated letters clear across the page."

"Will you _tell_ me?" I asked impatiently.

"Here goes then. You remember that I set down my theoretical key-sentence, thus:"

W O N F O R T O O F O R A T E

"The uncoding went along splendidly for eight places, thus:"

W O N F O R T O T H A N E C O U

"The rest was gibberish. It follows then that the running off the track must have happened at the ninth subst.i.tution and nowhere else."

"Obviously."

"The very morning that your letter about the library window arrived--that is, on June the twenty-first--I was sitting at my desk; for the ten thousand time, more or less, I printed out those distracting capitals:"

W O N F O R T O O F O R A T E

"As I looked at the line of letters I suddenly discovered something entirely new: the five end ones formed the perfectly good English word, _Orate_.

"There is a game, you know, in which you mix up the letters of a long word, such as _Plenipotentiary_, and then try to recombine them into subsidiary words, the biggest list winning the prize. Perhaps there were other esoteric or inside words in my key-sentence, a still deeper meaning and significance to this apparently haphazard collection of alphabetical symbols. I started experimenting, and almost immediately I did get another word, _Fort_. Now I'll write out the series again, using vertical lines to divide off the word-groups. Here it is:"

W O N

F O R T

O O F

O R A T E

"The only perplexity was in the third section, for although _OOF_ is a Yiddish slang word for money or cash it isn't much in use in our rural locality; in all probability, old Mr. Thaneford had never even heard of it. All the other words were good English.

"What was the ninth letter, the alphabetical rock upon which my fine theory had gone to pieces? Why it was none other than the second O in that very word, _OOF_. Then I saw the solution in a flash. Do you?"

I shook my head.

"There is another English work which corresponds phonetically to the number 2 or two. Of course it is _TO_. Let us make the subst.i.tution, thus:"

W O N

F O R T

O F

O R A T E

"A complete English sentence, you see. It doesn't make very good sense, but that is of no consequence, since it is merely what Chalmers calls er--er--well, what _do_ you call it, Chalmers?"

"Mnemonic guide," smiled Warriner. "An artificial aid to one's memory.

It would be somewhat easier to write down the key-letters correctly if this absurd sentence were kept in mind. You have to be absolutely accurate in the coding of a cypher message."

"Now then, Hugh, do you see?" demanded my wife.

"Of course I do," I answered eagerly. "The extra O in your original key-sentence is not only wrong in itself, but its inclusion in the series throws everything which follows it into hopeless confusion. Let's try it out."