'Old man, supposing young Trent to be alive and in duress somewhere, do you imagine that one man, or even two, could keep him day and night?'

'U-m-m—no.'

'Well, I said to Miss Jenrys an absurd thing. I said the letter might have been suggested by seeing those reward notices; but those notices did not give Mr. Trent's full name, and street, and number. No, sir, that letter was written by someone who has seen the contents of Gerald Trent's pockets, and who knows where he is, dead or alive.'

'But you don't think he means business?'

'No. And neither do you. If Trent is in the hands of the gang, no one out of the lot will be permitted to open the doors to him. Besides, do you think that a party of men who have the daring and the ability to keep a prisoner three weeks safely hidden will release him for a paltry ten thousand, knowing his father to be a multi-millionaire?'

'U-m-m—just so. And how do they keep him?'

'Well, to me that letter is very suggestive. It hints at a possible situation. It's hard to imagine how a young man, in possession of his strength and senses, could be held a prisoner here in Chicago. But let us say he is ill. Suppose, for instance, he was attacked, those diamonds he is said to have worn being the bait; he is injured; they search him and find him a valuable person to have and to hold. If he is ill they can keep him without much trouble. Or, the letter hints at insanity; suppose he was lured somewhere and drugged—kept drugged. An easy way to bring about insanity, eh?'

'Carl!' exclaimed Dave, with one of his sudden, decisive gestures, 'Carl, old man, I believe you've struck the trail! What's your next move?'

'My first move,' I corrected, 'will depend upon Mr. Trent. I can do nothing until I hear from him.'

'And then?' urged Dave.