Hi Col,
Wow, great job, thanks! Even if I am slightly ashamed at not finding that myself. :)
This set of Thurgars were quite interesting. Charlotte's parents had run a school in Paris I think, then a guest house in Algiers, and were friends with the Napier family.
Now, I have a letter somewhere from one of the Napiers talking about the Isle of Man, and Port Erin I think, and maybe a Mylchreest... I'll go look for it now, see if it has anything useful.