“Yes, the wooden rim of the button,” replied Muller, telling the truth this time. For he had held the little wooden circlet in his hands at the moment when the red light, reflected down from the mirrors, struck full upon his eyes. He had dropped it in his surprise and excitement. Franz found the little ring in the centre of the room where it had rolled, and the supposed electrician replaced it and rose to his feet, saying: “There, I’ve finished now.”
Franz did not recognise the double meaning in the words. “Yes, it’s all right! I’ve finished here now,” Muller repeated to himself. For now he knew beyond a doubt that the red light was a signal—and he knew also for whom this signal was intended. It was a signal for Herbert Thorne!—Herbert Thorne, whom no single thought or suspicion of Muller’s had yet connected with the murder of Leopold Winkler.
The detective was very much surprised and greatly excited. But Franz did not notice it, and indeed a far keener observer than the slow-witted old butler might have failed to see the sudden gleam which shot up in the grey eyes behind the heavy spectacles, might have failed to notice the tightening of the lips beneath the blond moustache, or the tenseness of the slight frame under the assumed embonpoint. Muller’s every nerve was tingling, but he had himself completely in hand.
“What do we owe you?” asked Franz.
“They’ll send you a bill from the office. It won’t amount to much. I must be getting on now.”
Muller hastened out of the door and down the street to the nearest cab stand. There were not very many cab stands in this vicinity, and the detective reasoned that Mrs. Bernauer would naturally have taken her cab from the nearest station. He had heard her return in her carriage, presumably the same in which she had started out.
There was but one cab at the stand. Muller walked to it and laid his hand on the door.
“Oh, Jimmy! must I go out again?” asked the driver hoarsely. “Can’t you see the poor beast is all wet from the last ride? We’ve just come in.” He pointed with his whip to the tired-looking animal under his blanket.
“Why, he does look warm. You must have been making a tour out into the country,” said the blond gentleman in a friendly tone.
“No, sir, not quite so far as that. I’ve just taken a woman to the main telegraph office in the city and back again. But she was in a hurry and he’s not a young horse, sir.”