Freeman had really thought Grace a fascinating girl, until he saw Miriam.

There was no harm in that: the trouble was, he had allowed Grace to perceive his admiration.
He had already remarked that she was a creature of violent extremes, tempered, but not improved, by a thin polish of subtlety.

She was now about to give an illustration of the passion of jealousy.

But it was not her jealousy that Freeman minded: it was the prospect of Miriam's scorn when she should surmise that he had given Grace cause to be jealous.
Miriam was not the sort of character to enter into a competition with any other woman about a lover.

He would lose her before he had a chance to try to win her.
But fortune proved rather more favorable than Freeman expected, or, perhaps, than he deserved.