You will need some names and dates.
Callow is a very popular Manx name. In the 1881 census of England, Wales and the Isle of Man, there were over 500 people named Callow who were Manx born.
Try www.familysearch.com for 1881 census and for births and marriages.
Or simply go to yahoo or google and type in:
Callow Isle of Man
and you will find a branch of the family.
There are Callows on the island.
Bruce