XXI—The Key-Word
Promptly at ten o’clock Marston walked into Carpenter’s office and sent in his card.
It found Carpenter pacing up and down, and frowning at a paper spread open on his desk. At the messenger’s apologetically discreet cough, he glanced around and took the extended card.
“Show him in!” he snapped, and swept the paper from the desk and into a drawer.... “Good-morning, sir!” as Marston bowed on the threshold; then, without any preliminaries: “What success?”
“I have the French code-book,” Marston replied.
“With you?”
Marston drew out the slender book. “It embraces all their codes, I believe,” he remarked.
“H-u-m!” said Carpenter thoughtfully, retrieving the paper he had just swept into the drawer. “How are we to work it, Mr. Marston?”
“As allies,” Marston replied. “I’m perfectly willing to let you have the book and everything in it, if you will let me have a copy of the letter. I’m confident that the key-word is here; I’m equally confident that the letter does not involve, either directly or indirectly, the United States. I understand that the letter is in the cipher of the Blocked-Out Square; in this book there are two pages and more of key-words to this Square, the last dozen or so of which are added in writing. If the letter is in that cipher, we should have no particular difficulty in finding the key-word. I would suggest, however, that we first try the last word on the list—maybe we won’t have to go any farther.”
“Very well,” said Carpenter, briskly.
The advantage was all with him. If Marston thought the letter was only a line and that he could remember the letters used, he was in for a shock. No man living could remember twenty spilled alphabets; and if he attempted to make a copy it could easily be prevented. The Fifth Secretary spread the paper on the table.
“Here is a copy of the cipher letter in question—we had it made large for convenience,” he explained. “The original is in the safe; you’ll wish to compare it with the copy, so we’ll have it here.”
He gave the necessary order; when the letter was brought he passed it to Marston.
“I’ll read the copy, if you’ll hold the original,” he said; and proceeded to call off the letters with amazing rapidity. “Correct, isn’t it?” as he ended.
“Yes!” said Marston returning the original to Carpenter. He wanted in every way to disarm suspicion; moreover, a copy could be made more readily from a large typewritten edition than from the small, written original. “Now for the code-book and the last key-word—à l’aube du jour, I think it is ... yes, à l’aube du jour, it is,” and he handed the book across. “Shall we try it first, Mr. Carpenter?”
“By all means,” said Carpenter. “Shall I set it down, or will you?”
One would never have imagined from his expression or his intonation that he had already tried à l’aube du jour for the key-word and failed; nor that why he had failed he now knew. The book was right as to the word, and the slip that Harleston had taken from Crenshaw’s pocket-book confirmed it. À l’aube du jour was not the key-word but the key-word was constructed from it by some arbitrary rule; and that rule was susceptible of solution. After he was free of this fellow Marston, he would solve the problem quickly enough. It was as sure as tomorrow. The prescience was come.
“About twenty letters should be enough for experiment?” he suggested, taking up a test card.
When he had written the key-word and the letters under it, he, scarcely without reference to the Blocked-Out Square, wrote the translation. Marston did the same, very much slower.
“It doesn’t fit!” Marston announced. “You can’t make anything out of AGELUMTONZN, and so forth.”
“I can’t!” Carpenter smiled—and waited. Would Marston suggest the transposed or elided word?
“I’m disappointed,” Marston confessed, “I thought sure we had it. Let’s try the next key-word in the book.”
They tried it, and the next, and all the rest. None of them translated the letter.
It took more than an hour; at the end, as a full measure of good faith and because it was of no further use to him—he having preserved a copy—Marston insisted that Carpenter retain the original of the French code-book and have a copy made, after which the book could be returned to him at the Chateau. During this hour and more his hand was in and out in his side coat-pocket. When he left the room there went with him, in that pocket, a copy of the original letter—roughly made by the sense of touch alone, yet none the less a copy and sufficiently distinct to be decipherable. For years Marston had practised writing in the dark and under all sorts of handicaps. In his pocket, a number of small slips of paper and a pencil were concealed. He would write a line, then take his hand from his pocket; after a time he would shift the page of paper, write another line, and then another, and so on until the copy was made. And all the while he was so frankly communicative, with apparently not the slightest intent to obtaining a copy—even tearing up the paper on which were the various trial translations—that he completely deceived Carpenter. When he left, the latter went with him to the elevator and bowed him down.
“I don’t quite understand their game,” Carpenter chuckled, as he turned away, “but it’s no matter. I took all the tricks this morning and still have a few trumps left. I thought he certainly would try for a copy of the letter, but he didn’t even attempt it. He may have committed it to memory, but I’ll chance it.”
Returning to his office he gave the code-book another careful inspection and confirmed his impression as to its being authentic. Then he laid it aside, and took up the letter and à l’aube du jour!
First he tried it in reverse position: ruoj ud ebua’l à. The translation was gibberish. Then he wrote the first and last letters, the second and next to last, the third and the third from last, and so on. The result, too, was gibberish. Next he dropped the first word, ‘à’ and tried the rest—still gibberish. He dropped also the ‘l’—still gibberish. Then, in turn, the ‘a’ of the third word the ‘d’ of the fourth, the ‘j’ of the last word—all gibberish. Next he wrote the key-word entire but transposed the ‘a’ from the first letter to the last— still gibberish. He began with the aube—still gibberish.
“Damn!” said he.
He was persuaded that the key-word was in the sentence before him; the code-book, Crenshaw’s slip of paper, and his own hunch were convincing, yet the combination was slow in coming.
Du jour à l’aube was the next arrangement. He wrote it under the printed words and began to apply the Square.
The D and the A yielded A; the U and the B yielded V; the J and the C yielded E; the O and the D yielded R; the U and the E yielded T; the R and the F yielded I.
“Averti!”
Carpenter gave a soft whistle of satisfaction. French, it was—his hunch had not deceived him. The key-word was found!
Swiftly he worked out the rest of the cipher, setting down the letters of the translation without regard to words. “Averti” was evident because it was the first word. At the end, he had this result:
AVERTIQUELALLEMAGNEAENGAG
EUNOFFICIERADECELERLAFORM
ULESECRETEDESETATSUNISEMP
LOYEEACOLLODONNIERLAFULMI
COTONPOURLAPOUDRESANSFUME
EALARTILLERIEDEGROSCALIBR
EETQUEMADELINESPENCEREMIS
SAIREDELALLEMAGNEAPARISPH
OTOGRAPHIECIINCLUSEAETECH
ARGEEDELARECEVOIRNESEPEUT
DECOUVRIRLENOMDUTRAITRESP
ENCERESTPARTIEPOURNEWYORK
SURLALUSITANIAQUIDOITARRI
VERLEQUATORZEATOUTEFORCEI
NTERCEPTEZLAFORMULEOUEMPE
CHEZAMOINSQUELALLEMAGNENE
LOBTIENNESPENCERSIMPORTAN
TEALAFRANCE
There was not the least doubt as to it being in French—the last three words, as well as the first, proved it; also that he had the correct key-word. It only remained now to separate the result into words. And this puzzle presented no difficulties to Carpenter; he quickly marshalled it into form:
“Averti que l’Allemagne a engagé un officier à déceler la formule sécrète des États-Unis employée à collodonnier la fulmi-coton pour la poudre sans fumeée à l’artillerie de gros calibre; et que Madeline Spencer, émissaire de l’Allemagne à Paris,—photographiè ci, incluse—a été de chargée la recevoir. Ne se peut découvrir le nom du traître. Spencer est partie pour New York sur la Lusitania qui doit arriver le quatorze. À toute force interceptez la formule; ou empêchez à moins que l’Allemagne ne l’obtienne. Spencer pas importante à la France.”
And under it he wrote the English translation: “Informed Germany has induced an officer to betray United States secret formula for colloding process of treating gun-cotton for smokeless powder for high power guns, and that Madeline Spencer, a German Secret agent in Paris, photograph enclosed herein, is delegated to receive same. Cannot ascertain name of traitor. Spencer sailed Lusitania, due New York, fourteenth. Take any means to intercept formula; or at least to prevent Germany obtaining it. Spencer not essential to France.”
Spencer not essential to France! Surely this woman had great power, either of knowledge or of friends; she resided in Paris, yet France was reluctant to lift hand against her so long as she was on French soil. Well, he would turn the matter over to Harleston; let him decide whether it was to be thumbs up or thumbs down for her Alluringness. Furthermore, the meeting with Snodgrass now assumed much significance. Snodgrass was an ex-army officer. Harleston must be warned at once.
He tried for him at the Collingwood, the Cosmopolitan, the Rataplan, and finally at the Chateau. He got him there.
“Can you come here at once?” he asked.
“Not well,” said Harleston, “I’ve an appointment.”
“Forget it!” Carpenter exclaimed. “I’ve found the key-word and made the translation. It’s serious—Very well, come right in; I’ll be waiting.”
Harleston scribbled a note to Mrs. Clephane and sent it up by a page; he would be back in half an hour; would she meet him in the Alley.