Matherfield groaned again, but the reason of his distress was obviously of a different nature.
"A mistake, sir—a great mistake!" he exclaimed, shaking his head at Penteney. "You shouldn't have let that fellow go like that! You should have handed him over there and then. Go? You don't know where he may be!"
"Oh, well, we're not quite such fools as we seem, Matherfield," he replied. "When I went down to Dorking with Lady Riversreade on Tuesday morning I had with me a smart man whom I can trust. He saw Baseverie arrive; he saw Baseverie leave. I think we shall be able to put our fingers on Baseverie at any moment. Our man won't lose sight of him!"
"Oh, well, that's better, sir, that's much better!" said Matherfield. "That's all right! A chap like that should be watched night and day. But now, gentlemen, about this reward! Your notion of offering it sprang, of course, from this Baseverie business. But—how, exactly? Did he mention Hannaford to Lady Riversreade?"
"No!" replied Blenkinsop. "I'll tell you how we came to issue the advertisement. All Sunday afternoon and evening, and for some time on Monday morning, Lady Riversreade, Major Penteney, and myself were in close consultation about this affair. I'll tell you at once how and why we connected it with the poisoning of Hannaford, of which, of course, all of us had read in the newspapers."
"Aye!—how, now?" asked Matherfield.
"Because of this," answered Blenkinsop. He tapped his desk to emphasise his words, watching Matherfield keenly as he spoke. "Because of this: Baseverie told Lady Riversreade that the gang of blackmailers had in their possession the original warrant for Mrs. Whittingham's arrest!"
Hetherwick felt himself impelled to jump in his chair, to exclaim loudly. He repressed the inclination, but Matherfield was less reserved.
"Ah!" he exclaimed sharply. "Ah!"
"Baseverie made a false step there," continued Blenkinsop. "He should never have told that. But he did—no doubt he thought a rich woman easy prey. Now, of course, when we came to consult, we knew all about the Sellithwaite affair; we knew, too, that Hannaford was superintendent at the time and that he had the warrant; it was not at all improbable that he had preserved it in his pocket-book, and had it on him when he came to London. What, then, was the obvious conclusion—that the men who now held that warrant had got it, probably by foul means, from Hannaford, and were concerned in his murder? And—more than that—did the gang of which Baseverie spoke really exist? Wasn't it likely that the gang was—Baseverie?"