r which the
Germans seem to have a positive genius. The chalk had been excavated for
trench building, the walls were boarded, and square balks of timber
supported the roof in a double row of pillars.

He could not count the cases of ammunition--there were so many--nor the
stacks of rifles that were stored in the place, but he saw enough to
convince him that he had made a very important haul, if only things were
going well above ground.

The distance he had fallen surprised him when he mounted the steps, but
the steel door resisted all his efforts to open it, and though he
thundered with his fists, there was no response from the other side.

"I've got to get out of this somehow," he thought, and, descending to
the floor again, he made a minute inspection of the vast dug-out without
finding any means of egress, until he came to an open case of rifle
ammunition, from which several packets of cartridges had been removed.

As he read the description printed on the others he felt cold air
blowing on him from somewhere not far away. At first he thought there
must be some hidden ventilation shaft, but the draught was low down and
fluttered the tatters of his abbreviated tunic.

"It's a jolly odd thing," he murmured, turning his light in the
direction of the current. "Surely there is not another dug-out below
this one?"

He passed round the angle of some piled-up boxes stamped with strange
hieroglyphics, and then he stood still, for there was another door, the
entrance to a gallery, as he saw in a moment.

But this time it led upward in a rather steep slope, and the floor was
marked with the print of heavy boots, showing that the passage had been
well used.

"I suppose it would take a month of Sundays to come across some revolver
ammunition, and then the chances are it wouldn't fit these French
chambers," he thought, examining the commandant's second revolver, which
had only one charge left. "Anyway, I must find where this leads to."
And, veiling the light with his fingers, he entered the gallery.

The sides had been roughly smoothed and faced by the pioneers' shovels,
and he shivered involuntarily, for it was cold.

Making no noise, he crept for some distance in a straight line, until he
came to a right-angle bend in the gallery, which he followed for sixty
or seventy yards, and then switched off his torch as a loud explosion,
not far ahead, seemed to drive the air against his cheeks, followed by
the acrid odour of