There is to best of my knowledge no place with a name similar to Truro (except possibly Thurot's cottage in Bride way up in north of the Island) - you can look at a good collection of local names (choose Onchan and Braddan for Douglas Area) at
www.manxnotebook.com/fulltext/pn1925/index.htm

There was an 8yr Wm Bridson in the Industrial home for destitute children in 1881 census.