I thought that there was Burke's Landed Gentry but that didn't appear for a while later. However, Im sure there were directories fo addresses just like there are telephone directories now, at least for the landed gentry. I should say there was a guide to the "big houses" in each county. And if she was looking for him in London, agan surely she knew his address in London? I am assuming that thtey spent a month or 2 togehter in London, him visiting her whereever he'd set her up, then he said he was visiting friends or going back to his home for a bit.. and he went on a series of visits and didnt return to London...