Even from the outside it was apparent that many strange things had been done to the staid and dignified house of Reynolds. A mass of aerials hung above the roof. Some new windows had been cut at the second floor and filled with glass of a peculiar reddish-purple tinge. A residence had been turned into a laboratory, in sharp contrast to the charming houses up and down the street and the church of gray stone that stood opposite. Beside the door, at the main entrance, a modest plate bore the legend: "Dr. Friedrich von Stein." Parker pressed the bell. Then he squared his broad shoulders and waited: a very miserable, very likeable young man, with a finely shaped head and a good set of muscles under his well cut clothes. He had brought his sketches, but he was uncomfortable with the portfolio under his arm. It seemed to contaminate him. * * * * * The door opened to reveal a blocky figure of a man in a workman's blouse and overalls. The fellow was pale of eye, towheaded; he appeared to be good natured but of little intelligence. The only remarkable thing about him was a livid welt that ran across one cheek, from nose to ear. Beside him a glossy-coated dachshund wagged furiously, after having barked once as a matter of duty. "May we see Dr. von Stein?" asked Parker. "If he is in?" "I will ask the Herr Doktor if he iss in," replied the man, stiffly. "_Dummkopf!_" roared a voice from inside the house. An instant later man and dog shrank back along the hall and there appeared in their place one of the most striking personalities Allen Parker had ever seen. Dr. Friedrich von Stein was inches more than six feet tall and he stood perfectly erect, with the unmistakable carriage of a well drilled soldier. He was big boned, but lean, and every movement was made with military precision. More than any other feature his eyes impressed Parker: they were steady, penetrating, and absolutely black. But for a thread of gray here and there his well-kept beard and hair were black. He might have been any age from forty to sixty, so deceptive was his appearance. "Come in, if you please," he said, before Parker could speak. Von Stein's voice was rich and deep, but with a metallic quality which somehow corresponded with his mechanical smile. Except for the guttural r's there was hardly a hint of the foreigner in his speech. "It is Mr. and Mrs. Parker, I believe? I am Dr. von Stein." * * * * * He stood aside for them to pass into the hallway, and while they murmured their thanks he shot a volley of German at the man, whom he called Heinrich. The frightened servant vanished; and the Parkers were taken into a living room furnished carelessly, but in good enough taste. Betty took her place on a couch, to which the doctor led her with a bow. Parker sank into an overstuffed chair not far from a window.