“But look, Tom.” Drew placed a thing of blue steel on the table. “Here’s the automatic that the little fellow with fiery eyes dropped. He’s the sort that shoots on sight. He may have done some shooting right here in town. It might just happen that you’ve got a bullet in your collection that came from his gun.”
“Might at that.” Tom took the gun. “Quite a collection of bullets I’ve got right now. There’s the one that stopped Patrolman O’Malley down by the Stock Yards. There’s the one that passed through the Chink’s heart and landed in a wall down in Chinatown. Six or seven more. I’ll try it out. Want to come along, Johnny?”
Johnny Thompson dropped the book he was reading. “I’ll be glad to!” Anything that had to do with scientific crime detection might claim this boy’s attention, be it day or night.
Tom Howe and Johnny dropped down to the basement where a bullet might be fired into a barrel of sawdust without disturbing the guests of the hotel. Drew finished his report, dispatched it by a messenger and then, having extinguished his lamp of gleaming white light, switched on one of faint blue that gave the whole place an air of spooky mystery. It was thus that he could best think out the problems which lay directly before him.
“A whole day gone,” he told himself. “And what have we? A bed sheet taken from a sleeping car. An invisible footprint on that sheet. But whose footprint? Shall we ever know? A bullet.”
He spread out a sheet of paper to examine it afresh. “A second message from the dead,” he murmured. “At least from the Galloping Ghost. Pretty hard-fisted ghost at that. Knocks Tom down; then when he is gone, digs a bullet from some post or railway tie, and presents it for our inspection. He says here that the bullet is the one fired at Tom out there by the Red Rover’s sleeping car. ‘Find that man.’ And then—sure, find him if you can!
“But this jack-knife business,” he mused on. “The Ghost says one of the kidnapers has the whittling habit, that while waiting for Red to fall asleep he sat on a pile of ties and whittled at a soft stick. A knife blade, he says, when examined under a microscope shows some irregularities on its edge, even the sharpest of ’em. I suppose that’s right. But what of it?”
He sat for some time in a brown study from which he emerged with a start and a low exclamation:
“Something to it! What? Might be a lot! I’ll have to get Tom digging into that. He and his microscope have solved many a baffling crime.”
Once again he settled back into meditation. “Speed boat tied up far down the river. Airplane hangar nearby. Police have searched all buildings near there. No result. Looks like an airplane job. Spirited away in an airplane. What could be simpler? Wonder if the night mechanic at the airport knows anything? If he does, like as not he wouldn’t tell.