Greg, Google sent me to Slater's Directory 1857 Castletown where I found three farmers located at similar sounding names. Samuel Keggin, Robert Cain and William Barrow. Checking my older map, and reading following and preceeding pages in the 1851 IOM Census, it would seem that their farms were located perhaps on the road up to Grenaby - Moaney Moare is the clue if you have a map.
Again good hunting.