Nancy Baym wrote:

A related note I've seen mentioned but can't remember where (Naomi Baron, are you here? you must know, it was probably you) is 19th century London where mail was delivered several times daily. Elizabeth Barrett Browning and Robert Browning apparently carried out their famed courtship through this mail in a way that parallels email. Nancy

I referred to all this in my paper, reference below. In mid- to late Victorian London, mail was delivered once every hour for 12 hours of the day (source: Asa Briggs, Victorian Things, Chicago: Univ. of Chicago Press, 1988). Danet, Brenda. 1997. "Books, Letters, Documents: the Changing Aesthetics of Texts in Late Print Culture." Journal of Material Culture 2:5-38. You have a good memory, Nancy! Brenda Danet