He rose, crushing the paper in his hand, and went out into the street.

There was only one way--to write.
This he did standing at the ink-bespattered shelf which served as writing desk in the post office.
"DEAR MARY: I have just received your letter.

It's a little late but perhaps it ain't too late.

Anyhow, I'm banking on this finding you just the same as when you wrote.

I wish I could visit you again but I'm afraid I couldn't do it a second time without being recognized, but write to me at once, and, if you say come, I'll come.