t thoroughly. Then Johnny searched the sides,
the abutments. He sent the gleam of his powerful flashlight into the
dark depths beneath, but all to no purpose. The man was gone.

"Humph!" said Johnny.

"Hisch!" breathed Hanada.

"Well, all I have to say," observed Johnny presently, "is that if the
old Chicago River has that fellow, he'll be cast ashore. The good old
Chicago doesn't associate with any such."

They stood there leaning on the wooden railing debating their next move,
when a shot rang out. Instantly they dropped to the floor of the bridge.
A bullet whizzed over their heads, then another and another. After that
silence.

"Get you?" whispered Johnny.

"No. You?"

"Nope."

Then a long finger of light came feeling its way along the murky waters
to rest on the bridge.

With a sigh of relief, Johnny saw that it came from a police-boat down
stream. The light felt its way back and forth, back and forth across the
river, then up to the bridge and across that. It came to rest as it
glared into their eyes. It blinked one, two, three times, then went out.

"I'm glad they didn't hold it on us," breathed Johnny. "In that light
anybody that wanted to could get a bead on us."

Hearing heavy, hurrying footsteps approaching, they stood up well back
against the iron braces.

"Police!" whispered Johnny.

"You fellows shoot?" demanded one of the policemen as they came up and
halted before the two boys.

"Nope," Johnny answered.

"No stallin' now."

"Search us," Johnny suggested. "The shots were fired at us, though where
from, blessed if I know. Came right out of space. We'd just searched the
bridge from end to end. Not a soul on it."

"What'd y' search it fer?"

"A man."

"W'at man?"

"That's it," Johnny evaded. "We wanted to know who he was."

The policemen conversed with one another in low tones for a moment.

"One of the bullets struck a cross-arm; I heard it," suggested Johnny.
"You can look at that if it'll be any comfort to you."

The policeman grunted, then following Johnny's flashlight, examined the
spot where the bullet had flaked the paint from the bridge iron.

"Hurum!" he grumbled. "That's queer. Bullet slid straight up the iron
when it struck. Ordinarily that'd mean she was shot square against it
from below and straight ahead, but that can't be, fer that brings her
comin' direct out of the river, which ain't human, nor possible. There
wasn't a boat nor a barge nor even a plank on the