"I am not easily shocked," said Beale.

He glanced at the professor.

"I see," said Parson Homo, rising, "that I am _de trop_. Unfortunately I cannot go into the street without risking arrest. In this country, you know, there is a law which is called the Prevention of Crimes Act, which empowers the unemployed members of the constabulary who find time hanging on their hands to arrest known criminals on suspicion if they are seen out in questionable circumstances. And as all circumstances are questionable to the unimaginative 'flattie,' and his no less obtuse friend the 'split,' I will retire to the bedroom and stuff my ears with cotton-wool."

"You needn't," smiled Beale, "I guess the professor hasn't many secrets from you."

"Go on guessing, my ingenious friend," said the parson, smiling with his eyes, "my own secrets I am willing to reveal but--_adios!_"

He waved his hand and passed behind the cretonne curtain and the old man looked up from his instrument.

"It is the Donovan Leichmann body that I search for," he said solemnly; "there was a case of sleeping-sickness at the docks, and the Herr Professor of the Tropical School so kindly let me have a little blood for testing."

"Professor," said Beale, sitting down in the place which Parson Homo had vacated and leaning across the table, "are you still working for van Heerden?"

The old man rolled his big head from side to side in an agony of protest.

"Of the learned doctor I do not want to speak," he said, "to me he has been most kind. Consider, Herr Peale, I was starving in this country which hates Germans and regard as a mad old fool and an ugly old devil, and none helped me until the learned doctor discovered me. I am a German, yes. Yet I have no nationality, being absorbed in the larger brotherhood of science. As for me I am indifferent whether the Kaiser or the Socialists live in Potsdam, but I am loyal, Herr Peale, to all who help me. To you, also," he said hastily, "for you have been most kind, and once when in foolishness I went into a room where I ought not to have been you saved me from the police." He shrugged his massive shoulders again. "I am grateful, but must I not also be grateful to the learned doctor?"

"Tell me this, professor," said Beale, "where can I find the learned doctor to-night?"

"At his so-well-known laboratory, where else?" asked the professor.

"Where else?" repeated Beale.

The old man was silent.

"It is forbidden that I should speak," he said; "the Herr Doctor is engaged in a great experiment which will bring him fortune. If I betray his secrets he may be ruined. Such ingratitude, Herr Peale!"

There was a silence, the old professor, obviously distressed and ill at ease, looking anxiously at the younger man.

"Suppose I tell you that the Herr Doctor is engaged in a dangerous conspiracy," said Beale, "and that you yourself are running a considerable risk by assisting him?"

The big hands were outspread in despair.

"The Herr Doctor has many enemies," mumbled Heyler. "I can tell you nothing, Herr Peale."

"Tell me this," said Beale: "is there any place you know of where the doctor may have taken a lady--the young lady into whose room you went the night I found you?"

"A young lady?" The old man was obviously surprised. "No, no, Herr Peale, there is no place where a young lady could go. Ach! No!"

"Well," said Beale, after a pause, "I guess I can do no more with you, professor." He glanced round at the cretonne recess: "I won't inconvenience you any longer, Mr. Homo."

The curtains were pushed aside and the aesthetic-looking man stepped out, the half-smile on his thin lips.

"I fear you have had a disappointing visit," he said pleasantly, "and it is on the tip of your tongue to ask me if I can help you. I will save you the trouble of asking--I can't."

Beale laughed.

"You are a bad thought-reader," he said. "I had no intention of asking you."

He nodded to the old man, and with another nod to his companion was turning when a rap came at the door. He saw the two men exchange glances and noted in the face of the professor a look of blank dismay. The knock was repeated impatiently.

"Permit me," said Beale, and stepped to the door.

"Wait, wait," stammered the professor, "if Mr. Peale will permit----"

He shuffled forward, but Beale had turned the latch and opened the door wide. Standing in the entrance was a girl whom he had no difficulty in recognizing as Hilda Glaum, sometime desk companion of Oliva Cresswell.

His back was to the light and she did not recognize him.

"Why did you not open more quickly?" she asked in German, and swung the heavy bag she carried into the room, "every moment I thought I should be intercepted. Here is the bag. It will be called for to-morrow----"

It was then that she saw Beale for the first time and her face went white.

"Who--who are you?" she asked; then quickly, "I know you. You are the man Beale. The drunken man----"

She looked from him to the bag at her feet and to him again, then before he could divine her intention she had stooped and grasped the handle of the bag. Instantly all his attention was riveted upon that leather case and its secret. His hand shot out and gripped her arm, but she wrenched herself free. In doing so the bag was carried by the momentum of its release and was driven heavily against the wall. He heard a shivering crash as though a hundred little glasses had broken simultaneously.

Before he could reach the bag she snatched it up, leapt through the open door and slammed it to behind her. His hand was on the latch----

"Put 'em up, Mr. Beale, put 'em up," said a voice behind him. "Right above your head, Mr. Beale, where we can see them."

He turned slowly, his hands rising mechanically to face Parson Homo, who still sat at the table, but he had discarded his Greek book and was handling a business-like revolver, the muzzle of which covered the detective.

"Smells rotten, doesn't it?" said Homo pleasantly.

Beale, too, had sniffed the musty odour, and knew that it came from the bag the girl had wrenched from his grasp. It was the sickly scent of the Green Rust!

CHAPTER XIII

AT DEANS FOLLY

With her elbows resting on the broad window-ledge and her cheeks against the cold steel bars which covered the window, Oliva Cresswell watched the mists slowly dissipate in the gentle warmth of the morning sun. She had spent the night dozing in a rocking-chair and at the first light of day she had bathed and redressed ready for any emergency. She had not heard any sound during the night and she guessed that van Heerden had returned to London.

The room in which she was imprisoned was on the first floor at the back of the house and the view she had of the grounds was restricted to a glimpse between two big lilac bushes which were planted almost on a level with her room.

The house had been built on the slope of a gentle rise so that you might walk from the first-floor window on to the grassy lawn at the back of the house but for two important obstacles, the first being represented by the bars which protected the window and the second by a deep area, concrete-lined, which formed a trench too wide to jump.

She could see, however, that the grounds were extensive. The high wall which, apparently, separated the garden from the road was a hundred yards away. She knew it must be the road because of a little brown gate which from time to time she saw between the swaying bushes. She turned wearily from the window and sat on the edge of the bed. She was not afraid--irritated would be a better word to describe her emotion. She was mystified, too, and that was an added irritation.

Why should this man, van Heerden, who admittedly did not love her, who indeed loved her so little that he could strike her and show no signs of remorse--why did this man want to marry her? If he wanted to marry her, why did he kidnap her?

There was another question, too, which she had debated that night. Why did his reference to the American detective, Beale, so greatly embarrass her?