Five seconds, fifteen seconds passed, then the long curtains before the window alcove gently parted and a man looked into the empty room. With head and shoulders protruding he waited until the sound of running water reached his ears, then advanced softly into the room. The desk was his objective point, and his nimble fingers made quick work of sorting its meager contents. His search was unrewarded; there was not a scrap of incriminating writing in any drawer, and the neat pile of blotting-paper was untouched.

The intruder's expression altered; curiosity gave way to doubt. Without wasting time he replaced every article where he found it, pausing occasionally to listen to the sound of splashing coming from behind the closed bathroom door. Convinced there was no immediate danger of interruption from that quarter, he walked swiftly to the closet and minutely examined Miller's clothing. Just as he was leaving the closet a box-shaped leather bag marked "Underwood" attracted his attention, and pushing aside a bundle of soiled underclothing, he knelt down and inserted a skeleton key in the lock, and after a second's work, forced back the wards and opened the lid of the box. The typewriter it contained proved uninteresting, and putting back everything as he had found it, he returned to the window by which he had entered. Pushing it open, he climbed out on the ledge and, closing the window behind him, by the aid of ropes swung himself over to a near-by fire escape and disappeared inside a room opening from it.

The slight sound occasioned by the closing of his bedroom window was drowned in Miller's cheery whistle as he emerged from the bathroom.

Refreshed and invigorated by his bath, he switched off the lights and climbed into bed.

The sunlight was streaming in the windows when he awoke, and it was a full minute before his sleepy senses grasped the fact that someone was pounding on the hall door. Hastily donning his bathrobe, he turned the key and opened the door. Henry, the Whitneys' chauffeur, was standing on the threshold.

"May I have a word with you, sir?" he asked.

"Certainly, come in," and Miller, conscious of his neglige attire and that two pretty women were passing down the hall, precipitously retreated into his bedroom. "Shut the door after you." He waited until his order had been followed, then demanded impetuously: "How is Miss Kathleen?"

"Better, sir."

"Thank God!" The fervid exclamation escaped him unwittingly, and a faint tinge of red stained his cheeks as he met Henry's attentive regard. "Did you give her my note?"

"I sent it to her by the nurse, sir; Miss Kathleen still keeps her room,"

said Henry respectfully. "Vincent tells me that she refused even to see her mother and father."

"Have you an answer for me?" as the servant paused.

"The nurse came to the kitchen and gave me these"--pulling a letter and package out of his pocket--"to deliver personally to you, sir; Miss Kathleen asked to have them sent at once."

Taking them Miller examined the addresses; the note was the one he had written Kathleen, and the package bore the label of a prominent jeweler, upon which was written Kathleen's full name in Miller's handwriting. Both were unopened. Miller placed them in his pocket with unmoved face.

"Why did you not deliver them to me last night?" he asked curtly.

"I started to, sir, but seeing you walking with Baron von Fincke down Massachusetts Avenue, sir, I...." Henry's eyes wavered and fell before Miller's scrutiny.

"Followed me?" prompted the latter, bending forward.

"Only a little way"--quickly. "I did not like to intrude, sir, and by following hoped to get a chance to give you Miss Kathleen's package and note. I lost sight of you at Thomas Circle, sir, and went home. That is the gospel truth, sir, as sure as my name is--Heinrich."

Miller viewed the chauffeur in silence. "So!" he exclaimed, and a pleased smile brightened his face. "Naturalized, or born in this country?"

"Born here, sir, of naturalized parents." The chauffeur twisted his cap nervously. "German-American, sir."

"There is no such thing, Heinrich." Miller's voice deepened. "The hyphen cannot be recognized. You are either American or German."

The chauffeur straightened himself, and his heels clicked together as he raised his hand in salute.

"Hoch der Kaiser!"

The words were echoed by Miller as he sprang forward and grasped the chauffeur's hand. "For the Fatherland!" he added in German. "Why have you not declared yourself before?"

"Until last night, Herr Captain, I was not absolutely sure you were one of us. But later in the evening Baron von Fincke...."

"Stood sponsor for me," finished Miller, thrusting his hand in his pajama pocket, and thereby pushing an envelope still deeper in it. "What have you to report? Wait, speak English; the walls have ears."

The chauffeur whitened and moved closer to Miller. "Was Mr. Spencer in your confidence?"

"No."

"And the Baron did not trust him," said Heinrich, reflectively. "If he was not one of us, how came he to be killed?"

"God knows." Miller threw out his hands in a hopeless gesture. "I don't."

"But there must be some motive for the crime," argued the chauffeur.

"Miss Kathleen must have suspected something before taking ..." Powerful hands on his throat choked his utterance.

"Never mention Miss Kathleen's name in that connection again," commanded Miller, his voice low and stern. "You hear me, you dog!" and he shook Heinrich until his teeth rattled, then released him.

"Pardon," gasped the badly frightened man. "I meant no offense."

"See that you follow my instructions hereafter."

"Yes, sir"--Heinrich caressed his throat tenderly, and looked at Miller with a new respect. "I was only going to mention, sir, that Mr. Spencer meddled in what did not concern him. I believe he suspected what I have come to believe."

"And what is that?"

"That this photography business is only a blind."

"A blind?" Miller looked thoughtfully at his companion. "Suppose you pull up a chair; wait, first hang your cap over the keyhole of the hall door."

While waiting for Heinrich to follow his instructions Miller seated himself. "A blind?" he repeated. "No, no, Heinrich, you are mistaken; Mr.

Whitney has invented a very perfect aeroplane camera, of that I am thoroughly convinced. And our country needs it...."

"Undoubtedly, sir," Heinrich almost stuttered in his growing excitement.

"But he has invented something that we need more...."

"What is that?"

"I don't know, sir."

Miller, who had been leaning forward in his eagerness, drew back. "Don't waste my time, Heinrich," he said roughly.

"Your time won't be wasted," protested the German. "Have patience and let me explain. I cannot manage this affair alone, I need assistance--and --you are a frequent caller at the Whitney house...."

"Well, what then?"

"Mr. Whitney may be persuaded to take you to his studio ..." the chauffeur hesitated.

"Proceed," directed Miller shortly. "You can count on me."

"Good," the chauffeur hitched his chair closer. "Day before yesterday I carried a telegram up to the studio. Not hearing any sound in the room, I carefully turned the knob of the door and found it unlocked. For months I have tried that door, hoping for just such luck," he interpolated.

"Opening it very softly, I saw Mr. Whitney standing with his back to me, and facing the muzzle of a rifle. I had only time to note that the rifle was braced on two iron brackets and that Mr. Whitney was holding a string which was attached to the trigger; when I saw a flash, the rifle's recoil--and Mr. Whitney still standing just where he was."

Miller stared incredulously at Heinrich, down whose face sweat was running; the man was obviously telling the truth--at least, what he believed to be the truth.

"Wake up, Heinrich," he said skeptically, and the chauffeur flushed hotly.