man's thoughts turned to his own affairs. The
stimulating influence of a prison upon conscience and self-scrutiny is
immense. David asked himself whether he had done his duty as the head of
a family. What despairing grief his wife must feel at this moment! Why
had he not done as Marion had said, and earned money enough to pursue
his investigations at leisure?

"How can I stay in Angouleme after such a disgrace? And when I come out
of prison, what will become of us? Where shall we go?"

Doubts as to his process began to occur to him, and he passed through
an agony which none save inventors can understand. Going from doubt to
doubt, David began to see his real position more clearly; and to himself
he said, as the Cointets had said to old Sechard, as Petit-Claud had
just said to Eve, "Suppose that all should go well, what does it amount
to in practice? The first thing to be done is to take out a patent, and
money is needed for that--and experiments must be tried on a large scale
in a paper-mill, which means that the discovery must pass into other
hands. Oh! Petit-Claud was right!"

A very vivid light sometimes dawns in the darkest prison.

"Pshaw!" said David; "I shall see Petit-Claud to-morrow no doubt," and
he turned and slept on the filthy mattress covered with coarse brown
sacking.

So when Eve unconsciously played into the hands of the enemy that
morning, she found her husband more than ready to listen to proposals.
She put her arms about him and kissed him, and sat down on the edge of
the bed (for there was but one chair of the poorest and commonest kind
in the cell). Her eyes fell on the unsightly pail in a corner, and over
the walls covered with inscriptions left by David's predecessors, and
tears filled the eyes that were red with weeping. She had sobbed long
and very bitterly, but the sight of her husband in a felon's cell drew
fresh tears.

"And the desire of fame may lead one to this!" she cried. "Oh! my angel,
give up your career. Let us walk together along the beaten track; we
will not try to make haste to be rich, David.... I need very little
to be very happy, especially now, after all that we have been through
.... And if you only knew--the disgrace of arrest is not the worst....
Look."

She held out Lucien's letter, and when David had read it, she tried to
comfort him by repeating Petit-Claud's bitter comment.

"If Lucien has taken his life, the thing is done by now," said David;
"if he has not