prompted to creep along to the further end of the gulley, where, to my
surprise, I saw that close to where I stood two panes of glass had been
neatly removed and laid aside.

Through the hole I gazed down into the interior of the shed, when I was
startled to see the small glow of an electric lamp in the hand of the
man of whom we were in search.

He was standing beside the long, spindle-shaped hull of a new submarine
boat which lay on a very elevated set of stocks on the far side of the
shed. Another boat similar, but not so nearly complete, lay at the
bottom of the dock alongside her.

As Karff with his electric lamp moved slowly and noiselessly along,
carefully examining England's newest submarine, which rumour had said
was the most silent and perfect craft of its kind, I was able to make
out vaguely that, differing considerably from photographs of other
submarines I had seen, the boat on the elevated stocks had a bow which
ran out into a kind of snout, while instead of the usual small circular
or oval conning-tower she had what looked like a long, narrow
superstructure running along the greater part of her length. This,
however, was much higher forward than aft. She seemed, too, to have a
great number of propellers.

I watched the man Karff making some rapid memoranda, and so occupied was
he with his work that he never looked upward. Had he done so, he would
certainly have detected my head against the sky.

In a manner which showed him to be fully acquainted with the
construction of submarine vessels, he moved to and fro, examining both
boats. Then, after about half an hour's minute investigation, he seated
himself upon a bench and with his little lamp shaded to throw no
reflection he took out a piece of paper and leisurely made a rough
sketch of England's newest war-craft, both side and horizontal views.

Leaving him thus occupied, I descended to Ray, and finding him secreted
near the water's edge, described what I had discovered.

"Good!" he exclaimed. "So I was not mistaken in that cryptogram after
all! We will allow the fellow to complete his work and then compel him
to disgorge his notes. They will furnish us with very excellent
evidence."

So we waited, keeping our eyes fixed upon the spot where he must
descend, and hardly daring to breathe lest we should prematurely alarm
him.

The Dockyard clock chimed three, but the spy had not emerged. After
another half-hour of watchful silence I saw that Ray