sake don't. I--I----"

"Ah!" laughed my friend. "So it is as I thought. You two blackguards,
with some of your friends, I expect, have been secretly preparing
for the destruction of the Forth Bridge on 'the Day'--as you are
so fond of calling it. The staples are already driven in, and the
unsuspicious-looking wire ropes, attached to which the boxes of
gun-cotton and other explosives are to be sunk between the four
caissons, are all in readiness. The boat from a German merchant vessel
off Leith, signalled at intervals by your assistant Klauber, has been
bringing up box after box of that dangerous stuff and landing it at the
bottom of this garden; so that within an hour of receiving the code-word
from your chief, you would be able to wreck the whole bridge and blow it
into the water!"

The spy endeavoured to pass, but seeing Ray's determined attitude, held
back, and my friend compelled him to lay down his weapon.

"Jack," said my friend, "just see what's in that box."

I at once investigated it, and discovered within only innocent-looking
tin boxes of English biscuits. The three tins at the top I lifted out
and placed on the floor, but those below I found were filled with
circular cakes of what looked like felt, about an inch in thickness,
each with a hole through it, and with a small cavity for the reception
of the detonator. I showed it to Ray, pointing out that, packed with
it, were several smaller tins, like boxes of cigarettes.

"Yes. I see!" he exclaimed as I opened one. "Those are the detonators,
filled with fulminate of mercury."

"Let us pass!" cried both the spies.

"Not before you are searched shall you leave this house!" was the quick
reply. "If you resist, I shall fire into one of those boxes of
detonators, and blow you to atoms."

"And yourselves also!" remarked Klauber, his face pale as death.

"It will at least prevent our secrets falling into your hands, and at
the same time bring the truth home to the British Government!" was my
friend's unwavering answer.

Next moment both men made a dash towards the door, but I had drawn my
weapon and was upon my guard. There was a flash, followed by a deafening
report, as Ray fired at the box, aiming wide on purpose.

Then the two spies, seeing that they had to deal with a man who was a
patriot to his heart's core, realised that their game was up.

Sullenly Scholtz put down his weapon, and I searched both men.

From the pocket of the exemplary waiter I