Go Ask Alice – What Really Went on in Wonderland

As I gather from some biographical readings, it was possible in the London of the late XIX and early XX century to send and receive letters twice (or three times ?) a day, i.e. it would be possible to make dinner arrangements for the same day by mail, which was convenient before there was a widespread telephone system. Which is to say, many of those nearly 100k letters are probably the equivalent of an "want to go out for lunch" email/SMS/whatever.