They never could talk as freely as they wrote, even upon the most indifferent subjects, though Gianluca seemed perfectly at his ease in conversation.

There was a sort of undefined restraint from time to time, together with the certainty that they would write what they really meant, within a day or two, and understand each other far better than by spoken words.
In Gianluca's case such a condition of things was natural enough.

He felt that she understood friendship when he meant love, and he was aware that he was progressing slowly but surely towards the freedom to say what was always in his heart, while his success must depend upon his wisdom and tact in not surprising her with a declaration of passion, in the midst of a discussion upon church history or modern systems of charity.

Compared with what he had felt in their former relations, he was happy, now, beyond his utmost expectations; and, in the relative happiness he had found, he was willing to be patient, rather than to risk anything prematurely.
It was more strange, perhaps, that Veronica should regard this growing intimacy as she did, for she had no under-thought of a future change to something else, as he had, and she was naturally simple in reasoning and direct in action.

Yet she could not but be aware that there was a sort of duality in their friendship, and she never confused the ideas they exchanged when in the one state--that is to say, when writing--with those about which they talked when an actual meeting brought them into the other.