oof of the new wing below.
This latter we did not concern ourselves with, as we knew it dated since
the wizard's day, but carefully examined the stone tiles and the further
leads without, however, any discovery resulting.

We were just about to give up our quest when Dick's quick eyes noticed a
chink in the lead that formed the channel or gutter for the rain water
leading either way to the gargoyles beneath the bartizans outside.

'Look here!' he cried. 'See the dim light showing! I swear it's a
glimmer of glass. Evidently this particular lead was meant to be drawn
aside and admit the light.' I hastened to the side and peered with him
into the dirt-laden crack.

Opening my pen-knife I scraped away the dirt and soon verified his
conjecture that there was glass below. 'You're right!' I cried in my
excitement. 'It is glass. Now let's search and see if we can find
anything like a hinge, or at least some indication that the lead could
be withdrawn at will.' We sought all along by the containing wall and
found that the lead did not end in a flat sheet, as is usual, against
the wall, but was turned over, and evidently continued below.

'It looks very much as if it was meant to roll up and be turned over
like a blind on a roller below,' I said to my companion.

'I'm sure of it,' Dick replied with conviction. 'I'll tell you what we
must do. We'll pull up the lead, make sure of the extent of the glass,
then go below and search for the wizard's cell from the exact indication
we shall then have of its whereabouts.'

'Right!' said I, 'that's the method.'

We set to work, and soon had doubled back a strip of lead a foot broad
from the centre till the glass ended by the bartizan on either side. We
could not pull the lead right back because of the iron steps, which had
evidently been inserted when the new wing was built, and now interfered
with our further action.

The glass was set in heavy leaded panes, which were so engrained with
the grime of centuries that we could discern nothing through them.

'We must search for the wizard's cell from below,' I said. 'If we cannot
discover it there we must return and break in from above.'

'Yes,' agreed Dick, 'it would be a pity to smash the roof in if we can
find an entry below without causing damage.'

The orientation was now easy, and as we studied the position from the
parapet we could select the towelled window below which fitted best with
the position of the glass roof.

The