Irving dismissed from his mind for the time being the mystery concerning the middle-aged man in civilian clothes who had followed him through the streets on two occasions. His fears regarding the incident were dispelled, for he felt that Blau, the intelligence operative on the opposite side of the street, would take care of that matter very efficiently. Everything was coming his way now, and he in his mission than he had felt at any other time walked alone; with greater confidence of success since landing with his parachute.

It was a ten minute walk to the quartermaster's headquarters. At the entrance of the building, his curiosity concerning the game of "shadow chase shadow" which he presumed to be going on behind him was aroused by a sudden reverting of his mind to the subject, and he turned and looked down the street by which he had come. There was Blau, half a square away, but the "middle-aged man in civilian clothes" was not in sight.

"I wonder if he got onto the fact that somebody was directed to watch him," Irving mused. "But that ought not to have stopped him. He had nothing to fear from an agent of another department if he was engaged in legitimate government business."

The spy delivered his requisition for a soldier's uniform and was given in turn an order on the supply house and directions how to reach it. Then he left the building and took a car for the place where he was to get his suit.

Blau took the same car, but the "shadow" he had been ordered to "shadow" was not there unless he had disguised himself so successfully that Irving was unable to recognize him. The operative appeared to be somewhat puzzled, too, but he made no sign of recognition to the soldier in enemy uniform, and the latter maintained a like pretense of unacquaintance.

An hour later the spy was clad in a first lieutenant's uniform and on his way back to the hotel. Blau kept within hailing distance of him, but his shadowing seemed to be futile, for the "middle-aged man in civilian clothes" had not appeared in any recognizable guise or disguise. Indeed, Irving was certain that nobody except the operative had followed him since he came out of the quartermaster's office and started for the store-rooms.

The applicant for an army uniform was required to enlist for service in the army before it could be supplied. Irving was not surprised at this, but he was very much surprised by the kind of uniform given him. It bore the insignia of a first lieutenant's rank.

"That's certainly generous on the baron's part," he said to himself. "I don't understand it. I didn't read his note to the quartermaster, nor the quartermaster's order. Maybe they would have afforded some explanation. Maybe I shall have to earn my rank and meanwhile will go about like an automobile for which a license has not been issued but bears a tag 'license applied for.' Maybe that's my case here-first lieutenant's commission applied for. It looks kind of irregular, but I suppose 'the baron' knows his business. Anyway, mine is a special case all around, however one looks at it."

When he filled out his enlistment papers, of course Irving signed the name of Adolph Hessenburg, late of Toronto, Canada, and on the "history sheet" that he had to fill out he entered data given him by the boy of the original tattooed cubist-art message. Then he was granted the use of a room where he discarded his Canadian uniform and put on his new Prussian military disguise.

He felt that he was disguised now as he at no time had hoped to be since planning his spy expedition into the heart of the kaiser's kingdom. He surely must have the full confidence of the Prussian officials with whom he had come into contact, or he would not have been elevated to the military rank and position of trust that now were virtually his.

Irving was particularly pleased with the ease he had experienced in picking up the idioms of the German language. He had an excellent memory and scarcely a word or a phrase that was taught to him at school or behind the Canadian lines, or that he had heard since landing with a parachute on territory held by the Prussian armies, had failed to make a lasting impression on his mind. Moreover, he was very quick to put ideas together and in that way get their associated significance; so that he skillfully "figured out" the meaning of not a few words that he had never heard before they were used in conversation with him by "the baron" and other persons with whom he came in contact. And he was almost as quick and skillful in his use of those same words for the expression of his own ideas.

After leaving the quartermaster's supply depot, Irving visited a haberdashery and bought several suits of underwear, shirts, collars, and socks, and then returned to the hotel. As he entered his room and deposited his bundles on the bed a funny thing happened.

He stopped short-true, he could not have gone much farther without falling over the bed, but nevertheless there was a decided "shortness" to his "stop."

"My goodness!" he exclaimed, clapping his hand to his appetite region. "I haven't had any breakfast yet."

Which being a sufficiently thrilling climax for the closing of a chapter, we will carry the reader over in suspense to the next.

CHAPTER XXXI
AT WORK IN THE SPY OFFICE

Irving laughed and felt hungrier than ever. The humorous relaxation afforded him great relief from the nervousness of his morning's activities, which had been associated enough with doubt and apprehension to make a coward run and a brave man extremely cautious.

"Well, that's a good one," the young pseudo-boche lieutenant continued in soliloquy. "Here it's nearly 2 o'clock and I haven't eaten my breakfast, and meanwhile I'd forgotten all about it. And I'm as hungry as a bear. I wonder if the British blockade has left enough food in the kaiser's kingdom, to fill up the vacuum inside of me. I think I'll go and find out. That'll be worth-while information to carry back to the Canadian commanders."

So out he went to a restaurant two squares away, where he had small difficulty in getting all he wanted to eat, the only qualification being that he had to pay prices so out of proportion to his income that he instinctively began to figure out the financial problem of how to make his salary carry him through to the end of the month.

"I'm starting out too swell," he concluded after several minutes' reckoning. "I'll have to eat at cheaper restaurants and get a cheaper room. That makes me think I don't know how much my room at the hotel is going to cost me; but it's bound to be pretty steep. Anyway, I don't care, so long as I can pull through on my salary. I don't want to carry any of this money with me when I go back to the other side of No-Man's Land."

Irving did not ask how much the hotel was charging for his room. He merely announced that he would check out that evening after engaging quarters in a comfortable rooming house in a semi-residence district near the Tiergarten. Economy was not the only motive that caused him to make this move. Being now in German uniform, he reasoned that he might be able to throw off of his trail the "middle-aged man in civilian clothes" who had been shadowing him, if he changed his living address also. As a further precaution he made this change late in the evening.

Next morning he reported for duty at the office of "Mr. Herrmann" as he had been instructed by "the baron" to do. Mr. Herrmann proved to be in charge of a suite of offices in the intelligence building in which were employed more than a hundred persons, most of them men, varying in ages from 20 to 70. Irving, for want of detailed information regarding their duties, classed them all as clerks, stenographers and typists at first glance, and this in general was a very good classification, although many of them performed special work that entitled them to ranking positions of greater dignity. And he had not been employed there more than two or three days when he learned that half of them held such ranking positions together with salaries proportionate to the grades of work they did.

"Can you operate a typewriter?" asked Mr. Herrmann after conducting the new employe through one large and several smaller work-rooms under his superintendence.

"With two fingers," Irving replied with a smile.

"Learned it at home, eh? Well, you won't need a lot of speed. I understand your education in German is not very far advanced."

"Not very far," the spy replied.

"Can you read the script?"

"Yes, I can work it out. I know the letters, but they come to me rather slowly."

"You'll make it all right after a few days' practice. I'm going to set you at work first copying some translated cipher messages." (The boy's heart began to thump eagerly, but the thumping became a weaker reflex pattering as the superintendent continued.) "They don't amount to much. We get masses of indifferent material from numerous sources, but we keep it all carefully cataloged, indexed, and cross-indexed several times. Any little insignificant item of information may be worth a good deal to us at any time. That's one secret of the great value of the German spy system. Now I'll leave you with this budget of communications and let you work it out with your own intelligence. That's one way we have of finding out what a man is worth."

Irving longed to ask him how he protected such an intricate system of concentrated information from leaks that might be of value to the enemy, but wisely refrained.

"I'll find that out by keeping my eyes and ears open," he told himself. "I mustn't ask any questions except such as bear directly on my duties and are calculated to promote my efficiency."

He sat down at the desk assigned to him and was soon diligently, eagerly at work. His eagerness, however, was a well-camouflaged secret.

CHAPTER XXXII
A STARTLING RECOGNITION

For two weeks Irving continued his work in the record offices of the great German espionage system. His experiences there during this time were without special incident, except that they evolved before his mind a continuous motion picture of scientific detail far more intricate, comprehensive, and deep-reaching than he could ever have imagined.

There could be no doubt that "the baron," Mr. Herrmann, and the staff of experts, clerks, stenographers, and typists looked upon the "parachute hero" as a bona fide fatherland loyalist. The story of his "camouflaged escape" by parachute from an enemy aeroplane to deliver a cryptic-code message that he carried all the way from America had circulated among them, and the glee with which they commented on his skill and success indicated the intense feeling with which they, one and all, regarded the cause for which the Teutonic race was fighting-the supremacy of the empire founded by Prince Bismarck. Irving discovered also another important human factor in this relation, namely, that the initiated members of the great spy organization of the central powers could discuss among themselves the secrets of their system without becoming in the least gossipy; hence, the danger of their inadvertently dropping hints of important state matters never intended for "outside ears" was small indeed.

A more secretive group of employes it would be difficult to imagine. Moreover, their secrets seemed to be grouped in sections and degrees. And the most peculiar feature of the whole system, perhaps, was the fact that few instructions were given, defining these sections and degrees. Irving received none himself, and in all the time he was connected with the bureau he learned of nobody else who had been told what, or what not, to do or say in this regard.

"Here seems to be another instance of the requirement of instinctive understanding," he told himself a good many times. "They seem to give me credit of being an extremely intelligent fellow. Well, I hope I exceed their estimate of me. If I do, they may find it necessary co revise their system somewhat."

The degrees of secrecy Irving learned in the course of a week or more were of a graduated character. For instance, he soon discovered that he might talk about his own work to any and all other members of the force, but all of them outside of his class would not discuss their work with him. After he was advanced to the next higher grade of work he found, as he had already had reason to suspect, that there were two degrees of the great spy system within the "circumscribed freedom" of his intelligence. This "freedom" was circumscribed by a prohibition, forbidding him to discuss any spy subject to anybody outside the office except on special direction from superior authority.

Irving progressed rapidly in his work. He exhibited such ready comprehension of details and purposes that he was soon marked by the entire office force as a "coming man" in the government secret service. Undoubtedly his spectacular method of transit from the Canadian to the German lines helped materially to boost along his growing reputation, but it would also be unfair to put too much emphasis on this feat of daring and skill. Irving really deserved much credit for innate ability.

In his efforts to create a general feeling of satisfaction and confidence in order to ward off any suspicions which might arise regarding his purpose and motives, the young spy did a good many things that almost caused in him a rebellious boiling over of patriotic sentiment. He did much to perfect a filing system that had been neglected because of illness of the man previously in charge, and offered a number of suggestions for certain other efficiency improvements which brought forth complimentary notice from Superintendent Herrmann. But all the time, while doing these things, Irving kept in mind the big purpose of his mission which outmeasured so greatly in importance his services to the enemy that his feelings of self-reproach for the aid he was incidentally giving the kaiser's spy machine were short-lived.

Evidently it was the purpose of Mr. Herrmann to advance his spy pupil as rapidly as possible. Undoubtedly he was under orders to do this from "the baron." Although the reason for this method of procedure had not been stated in so many words, the understanding seemed to be clear enough that it was the purpose of the department to send him back to America equipped for very important work at an early date.

Three weeks after he entered the office he began to accumulate the information for which he had been sent. He then was given access to the card-index system of the great world-spy organization. It was like a city-library catalog, with references to files of interminable data buried away in metal boxes in a large vault.

In his work with this catalog and files he was associated with a man whose countenance was strangely familiar to him from the first. He tried to assume that there was merely a resemblance in the face of this man to that of some other man he had known on the Canadian front or at home, but such assumption failed to satisfy him. He could not drive away the feeling that he had met this fellow somewhere since he dropped from the sky with a parachute behind the German battle lines, but although he studied over the matter for hours while busy with his work he was unable by such efforts to solve the mystery.

The solution came during a period of relaxation, as the solution of many mysteries come. On the third day since his last advancement in the service, while making entries on certain catalog cards, there recurred to him a mental picture of his experiences with the unidentified man who had shadowed him through the streets while he was still in Canadian uniform. Two weeks before he had dismissed this incident from his mind, being convinced that the man had given up his quest, whatever it was.

But the returned picture did not rest long peacefully in his mind. It was followed closely by a thrill that almost made him drop the card that he held in his hand. He looked quickly, almost involuntarily, at his associate worker, who was bent over a task at his desk.

Irving knew at once that he was not mistaken. Before him was the "middle-aged man in civilian clothes" who had shadowed him more than three weeks before from the intelligence building to the hotel where he was living and to other places in the city.

CHAPTER XXXIII
A SURPRISING OFFER

Emil Strauss was the name of Irving's coworker in the card index room. One could hardly say that he was either an agreeable or a disagreeable fellow. He had little to say. It was generally understood that he was very efficient in his work and ranked as one of the leading, if not the leading, experts in the department.

Strauss was not a typical Teuton in appearance. Irving thought he looked as much like an Irishman as a German, that he might have passed for either or a Swede. He was of medium height, somewhat slender of build, and had a smooth, round face, out of which shone two piercing black eyes-that is, they shone and pierced when the camouflage of heavy eyelashes and eyebrows was lifted. Otherwise one would have noticed almost everything else about him first.

There was no doubt in Irving's mind as to his identification, but he caught not even a surreptitious glance of recognition from the fellow at any time. He attended strictly and diligently to his own business, and the spy did likewise from the moment of his recognition of the man. He was determined his new associate should see no evidences of uneasiness in him as a result of this development.

Three days elapsed after Irving's last advancement to the card-catalog division, and still the conversations between him and his working companion were of the "yea, yea, nay, nay" character. Finally, however, the boy decided to attempt to draw Strauss into conversation. He did this by reference to humorous incidents in the war as brought out in cartoons and pointed paragraphs in Berlin newspaper and magazines.

He was somewhat surprised, and pleased also, to note that the "middle-aged man in civilian clothes" did not meet his advances with coldness or indifference. The fellow proved, indeed, to be much more polite than it had at first seemed possible. He appeared to enjoy Irving's palaver, for the youth was something of a wit, but preferred to listen rather than talk himself. Finally, however, he grew more communicative and manifested something of interest in his associate's personal affairs.

"They're telling some great stories about you around here," he said one day as they were preparing to go out for lunch. It was the first time they had quit work for the noon hour at the same time. Usually Irving went first and his companion went out after he returned, although Strauss was virtually "his own boss" and came and went as he chose.

"Yes, they're a bunch of gossips around here," Irving replied with a deprecating smile. "And you know what magnified stories gossips turn out when their tongues get busy."

Strauss smiled mysteriously and said:

"Oh, for that matter we are all gossips, even the quietest of us sometimes. All you have to do is to get us off on the subjects that we are well informed about and you'll soon find out how our tongues can wag at both ends."

"It's pretty hard for me to imagine your tongue wagging at both ends," Irving returned with more meaning in his mind than he expressed in his tone of voice.

"Why?"

"Because you seem to enjoy listening more than talking."

"I am engaged in a secret business," Strauss explained, lifting his shaggy brows slightly and darting a sharp glance at the other.

"Yes, so am I," Irving returned quickly. "But I like to talk."

"So I observe," said Strauss with veiled significance, which the boy did not try to penetrate.

"Just to be sociable," the spy added by way of explanation and to prevent the conversation from lagging.

But Strauss did not appear to be so talkatively eager. They were in the locker and wash room during most of this exchange of words, and nothing further was said between them until they were outside the building. The catalog expert then spoke first.

"Where do you eat?" he asked.

"Oh, any place," Irving replied. "I've been in two or three restaurants around here. There's a good one down in the next block."

"That suits me," said Strauss.

They walked along in silence half a square, and then the boy's mysterious companion put to him the most inquisitive query that the spy had listened to from this man since he became acquainted with him:

"When do you expect to go back to America?"

"Good!" Irving said to himself. "Sounds as if he's going to open up. Maybe I'll get something out of him after all."

He little dreamed how much that something was going to be.

"I don't know," he answered aloud. "I haven't received any orders yet."

"You'd better begin to find out then," was the expert's advice uttered in tones of startling sharpness. "I suppose you know it's up to you to decide that matter yourself."

"Oh, yes, I suppose so," Irving replied with a matter-of-factness of manner, which was anything but expressive of what was going on in his mind. The fact is, he was a little disturbed by the last remark of his companion.

"I'll have to undergo a surgical operation before I start back," he added.

"What's that?" inquired Strauss. "Were you wounded?"

"No," Irving replied. "But I must get rid of a mark of identification and go back as another person."

Strauss nodded a stoical sign of interest. They were now at the entrance of the restaurant for which they were headed, and the conversation ceased until they were seated at a table in one corner of the room and well removed from other lunchers. After they had been served they resumed their discussion of Irving's proposed operation in subdued tones.

"It must be a curious growth on your body that you should have to remove it in order to avoid identification," Strauss remarked as he spread a "knife-end" of war-time "butter" on a piece of black bread.

"No, it isn't a growth," Irving replied. "It's that cubist art picture on my arm."

"Oh, I see," Strauss grunted. "But," he added, "I don't just see how an operation there is going to do you much good. What are you going to have done-have your arm cut off?"

"No-have the skin peeled off."

"Ach," grunted the card-catalog expert. "That will leave a scar."

"Not if I have some other skin grafted in its place."

"Quite an idea. Where do you expect to get the other skin to graft there?"

"From some part of my body," Irving replied.

"Ja wo-ohl," said the other slowly, with a suggestion of doubt in his voice not contained in the phrase. "But that would leave a scar on your body, and if some sharp fellow tried to identify you as the person who brought that tattooed message ever here the scar might help him to explain the disappearance of the picture on your arm."

"Yes, that's true," Irving agreed. "But the chance of anything of that sort is small. Anyway, I'd have to find somebody who would give me a section of his skin four inches by two."

"There are thousands of patriotic Germans who are willing to give their lives for their country," reasoned the expert. "It ought not to be hard to find somebody who would give a few inches of skin."

"You are very logical," the spy observed. "Perhaps there's somebody in our office who would make such a sacrifice for his country."

"I'll do it myself," declared Strauss quickly.

In view of the fact that the latter appeared a few weeks previously to have regarded him with very grave suspicion, Irving had to admit to himself after this offer that the spy-cataloger was more of a mystery than ever.