Can we somehow estimate the average speed of a ground+sea travel between Frankfurt and London in the beginning of 19th century?
I was more than surprised (if not shocked) to find in the beginning of Naill Ferguson's The House of Rothschild a cited part of one of letters sent by head of a family to one of his sons, where he says that the other brother from Frankfurt would like to join the first brother in London and that such trip would take three weeks.
This happens in post-industrial revolution times (beginning of 19th centry) so, even though I'm not a specialist in history of engineering, I was more than sure that with a steam power to both railroads and ships, such trip couldn't take more than a week, maybe five days at most -- 2-3 days for crossing Germany and 1-2 days for crossing the sea.
What am I missing? How could < 800 km track, that takes up to 9 hours by car today, take fifty times more (21 days) just two hundred years ago?