pped into
a small dinghy tethered there. At his word the others came running, and
with Wrington at the oars they also crept about in determined search.

"It's hopeless," growled Green, in an undertone. "On a night like this
we might as well look for a needle in a haystack."

"We won't give up yet, anyway," retorted Foyle, and there was an
unwonted irritability in his tone. "We've mucked it badly enough, but
I'm not going to fling it up while there's a sporting chance of finding
him. Do you think he'll be able to swim across the river, Wrington?"

"It would need a good man to do it in his clothes. The tide's running
pretty strong. More likely he's let himself drop down below the bridge,
and will try to pull himself aboard one of these craft."

Heldon Foyle rubbed his chin. Every moment their chances of catching the
fugitive lessened. In the darkness, which the lights from the bridge and
from adjacent boats only made more involved, there was little hope of
finding the man they wanted. He had not been seen from the moment of the
first plunge, and there were a score of places on which he might have
taken refuge, and where, now that he was warned, he could dodge the
searchers. He might have committed suicide, it was true, but somehow
Foyle did not think that likely.

For two hours the search continued, and then Foyle, chilled to the bone,
decided that it was hopeless. Wrington hailed the other boats, and the
detectives returned to the barge. A light thrown into the tiny cabin
disclosed amid the disorder an open kit-bag full of linen. Green pulled
out the top shirt and felt its texture between thumb and finger. Then he
pointed to the name of a West-end maker on the collar.

"Yes, it's hardly the kind of thing a barge watchman would wear,"
commented Foyle. "We'd better take the bag along, and you can go through
it at your leisure. The laundry marks will tell whose they are. You had
better stop here, Wrington, and take charge. Find out whom the barge
belongs to, and make what inquiries you can. Better have it thoroughly
searched, and report to me in the morning. Use your discretion in
detaining any one who comes aboard."

One of the motor-boats took Foyle and Green back to Scotland Yard. Both
were glum and silent: Foyle because his plan had miscarried at the very
moment that he had reached the keystone of the problem; Green because it
was his natural habit. It was easy enough to realise now that the whole
question was on