You will be sure of that always.

Will you not be sure of it?
"But you must not write a line in answer, not even to give me your assurance.

That must come when we shall meet at length,--say after a dozen years or so.

I shall tell mamma of this letter, which circumstances seem to demand, and shall assure her that you will write no answer to it.
"Oh, Harry, you will understand all that I might say of my feelings in regard to you.
"Your own, FLORENCE." This letter, when she had written it and copied it fair and posted the copy in the pillar-box close by, she found that she could not in any way show absolutely to her mother.

In spite of all her efforts it had become a love-letter.