Though Jack spoke coolly enough, he was feeling just a little nervous himself. From the hall beyond came a quick, buzzing noise, like a muffled circular saw, which resolved itself presently into the wild whirling of the handle of the telephone, as if some one were trying to get a call in a desperate hurry. Rigby jumped at once to the explanation, and Jack proceeded immediately to make a close examination of the room.
He was still in the act of doing so, when a startled cry from Rigby brought him up all standing. An instant later and Anstruther was there, demanding to know the meaning of this unwarrantable intrusion. Rigby congratulated himself upon his disguise; he had no fancy at that moment to be recognized by Anstruther.
"Who is that loafer yonder?" Anstruther demanded passionately. "What is the blackguard doing in my study? And, if it comes to that, what are you doing here too?"
Jack proceeded to explain exactly what had happened. In spite of the confusion of the moment, he had not failed to notice the fact that the music had ceased directly Anstruther had entered the room. It was quite evident that Anstruther had not the slightest idea of Rigby's identity. He was clearly taken in by the story of the fire, and pitched Rigby a half-crown, which the latter acknowledged hoarsely, after the manner of the class he was made up to represent.
"Well, I suppose it is all right now," Anstruther muttered. Usually cool and collected enough, he looked white and very much agitated. Something had evidently gone terribly wrong with that man of blood and iron. "Get these fellows out of the house, please, Masefield. I have had a great deal to worry me to-night, and I want to be quiet."
There being nothing further to wait for, and Rigby, having practically gained his point, departed with an intimation to Jack that he would wait outside for him. Masefield could see that Anstruther was regarding him with an eye of deep suspicion. But it was no cue of Jack's to notice this; he w r anted to make matters as smooth as possible.
"I suppose you were not very faraway?" he said. "I heard your violin a few minutes before the fire broke out. I wonder you did not see it for yourself."
Anstruther's face cleared slightly, though Jack noticed that his hand trembled, and that his pallid lips were twitching. With a commonplace expression or two, Jack turned and left the house as if nothing out of the usual run had happened. He found Rigby patiently waiting for him at the corner.
"Well, what do you think of that?" Rigby asked. "I am exceedingly glad to find that Anstruther did not recognize me. A most unlucky thing that he should have come back like that. Given a half-an-hour alone in that room, it would have been an odd thing if we had not solved the mystery of the invisible musician. But it is hardly safe to stop and discuss the question here. Walk on to the Planet office, and wait for me there."
"Is there any more to be done to-night?" Jack asked, when he and his friend were alone once more, seated in the latter's office. "Shall we stop here, or do you want to proceed further before you go to bed?"