Dacres sat in silence for a long time, breathing hard, and puffing violently at his cigar.

Hawbury said nothing to interrupt his meditation.

After an hour or so Dacres tramped off in silence, and Hawbury was left to meditate over the situation.
And this was the result of his meditations.
He saw that Dacres was greatly excited, and had changed completely from his old self.

His state of mind seemed actually dangerous.

There was an evil gleam in his eyes that looked like madness.