ng of bally mermaids. Why, we were almost level with the wharf when we
left, and if they came from BELOW that, as you say, they must have been
below water!"

"There they are, anyway," growled Stringer.

Mile after mile that singular chase continued through the night. With
every revolution of the screw, the banks to right and left seemed
to recede, as the Thames grew wider and wider. A faint saltiness was
perceptible in the air; and Stringer, moistening his dry lips, noted the
saline taste.

The shipping grew more scattered. Whereas, at first, when the fog had
begun to lift, they had passed wondering faces peering at them from
lighters and small steamers, tow boats and larger anchored craft,
now they raced, pigmy and remote, upon open waters, and through the
raindrift gray hulls showed, distant, and the banks were a faint blur.
It seemed absurd that, with all those vessels about, they nevertheless
could take no steps to seek assistance in cutting off the boat which
they were pursuing, but must drive on through the rain, ever losing,
ever dropping behind that black speck ahead.

A faint swell began to be perceptible. Stringer, who throughout the
whole pursuit thus far had retained his hold upon the man in the bows,
discovered that his fingers were cramped. He had much difficulty in
releasing that convulsive grip.

"Thank you!" said the man, smiling, when at last the detective released
his grip. "I'll admit I'd scarcely noticed it myself, but now I come
to think of it, you've been fastened onto me like a vise for over two
hours!"

"Two hours!" cried Stringer; and, crouching down to steady himself, for
the cutter was beginning to roll heavily, he pulled out his watch, and
in the gray light inspected the dial.

It was true! They had been racing seaward for some hours!

"Good God!" he muttered.

He stood up again, unsteadily, feet wide apart, and peered ahead through
the grayness.

The banks he could not see. Far away on the port bow a long gray shape
lay--a moored vessel. To starboard were faint blurs, indistinguishable,
insignificant; ahead, a black dot with a faint comet-like tail--the
pursued cutter--and ahead of that, again, a streak across the blackness,
with another dot slightly to the left of the quarry...

He turned and looked along the police boat, noting that whereas, upon
the former occasion of his looking, forms and faces had been but dimly
visible, now he could distinguish them all quite clearly. T