ribe, to the gaoler. But Laurent did not relax his vigilance, and every
morning one of the archers went round the cell with an iron bar, giving
blows to walls and floor, to assure himself that there was nothing
broken. But he never struck the ceiling, a fact which Casanova resolved
to turn to account at the first opportunity.

One day the prisoner ordered his gaoler to buy him a particular book,
and Laurent, objecting to an expense which seemed to him quite needless,
offered to borrow him a book of one of the other prisoners, in exchange
for one of his own. Here at last was an opportunity. Casanova chose a
volume out of his small library, and gave it to the gaoler, who returned
in a few minutes with a Latin book belonging to one of the other
prisoners.

Pen and ink were forbidden, but in this book Casanova found a fragment
of paper; and he contrived, with the nail of his little finger, dipped
in mulberry juice, to write on it a list of his library--and returned
the volume, asking for a second. The second came, and in it a short
letter in Latin. The correspondence between the prisoners had really
begun.

The writer of the Latin letter was the monk Balbi, imprisoned in the
Leads with a companion, Count Andre Asquin. He followed it by a much
longer one, giving the history of his own life, and all that he knew of
his fellow-prisoners. Casanova formed a very poor opinion of Father
Balbi's character from his letters; but assistance of some kind he must
have, since the gaoler must needs discover any attempt to break through
the ceiling, unless that attempt was made from above. But Casanova soon
thought of a plan by which Balbi could break through _his_ ceiling,
undiscovered.

'I wrote to him,' he relates, 'that I would find some means of sending
him an instrument with which he could break through the roof of his
cell, and having climbed upon it, go to the wall separating his roof
from mine. Breaking through that, he would find himself on _my_ roof,
which also must be broken through. That done, I would leave my cell, and
he, the Count, and I together, would manage to raise one of the great
leaden squares that formed the highest palace roof. Once outside _that_,
I would be answerable for the rest.

'But first he must tell the gaoler to buy him forty or fifty pictures of
saints, and by way of proving his piety, he must cover his walls and
ceiling with these, putting the largest on the ceiling. When he had done
this, I would