it ran. Again the wait, and again the staccato reply.
"Unlikely, but will send round to-morrow to make sure. Good-night."
As the instrument clicked its farewell, T. B. executed a silent war-dance to the scandal of the solemn operator, and the delight of the little captain.
"T. B., you'll get me hung!" he warned. "You'll upset all kinds of delicate instruments, to say nothing of the telegraphist's sense of decency. Come away."
"Now," demanded Captain Almack, when he had led him to his snug little office; "what is the mystery?"
T. B. related as much of the story as was necessary, and the officer whistled.
"The discovery I was trying to make," T. B. went on, "was the exact location of N.H.C. I asked him or them to come to Paris. As a matter of fact, I wanted to know if they were within twenty-four hours' distance of Paris. 'Impossible,' they reply. But they will come to Madrid, and offer to meet the Sud Express. So they must be in Spain and south of Madrid, otherwise there would be no impossibility about meeting me in Paris to-morrow. Where are they? Within reach of Gibraltar apparently, because they talk of sending round to-morrow. Now, that phrase 'sending round' is significant, for it proves beyond the shadow of a doubt exactly in what part of Andalusia they live."
"When people who live within reach of the fortress talk of going to Gibraltar, as you know they either say that they are 'going across to Gibraltar' or that they are 'going round.' By the first, they indicate the route _via_ Algeciras and across the bay; by the latter, they refer to the journey by way of Cadiz and Tangier----"
"Cadiz," repeated T. B. He bent his head forward and rested it for a moment in his hands. When he lifted it, his face was grave.
"It's worth trying," he muttered. "And," he continued aloud, "it will be bringing down two birds with one stone."
"Can I use the instrument again?" he asked.
"I'm going to Scotland Yard, and I shall not be away for more than ten minutes," he said; and in a few seconds he was crossing Whitehall at a run.
He passed through the entrance and made straight for the big bureau, where day in and day out the silent recorder sat with his pen, his cabinets, and his everlasting _dossier_.