try http://www.ee.surrey.ac.uk/Contrib/manx/catalog/b022_wm.htm for Beaconsfield tower (it was a windmill which were very unusual on the Island) - in 1870's it had only just stopped active use
re Capt Marsh see http://www.ee.surrey.ac.uk/Contrib/manx/fulltext/sx1925/jmarsh.htm for photo