Thank-you Roy for your information. I have looked through my files and can't find any Johns of around that time which could be likely for your search. I have a John Casement born 1792, Lonan, married to Catherine Whyte but they stayed on the island and had a large family including Robert of the Laxey wheel.
One possible link between the Casements of Lonan and Lezayre is Robert Casement Born 1725, Lezayre, possibly died 1808 in Lonan. He married Susannah als Burne. One of his children, John born around 1759 married Jane Kinley and they were the parents of the John I mentioned above.
As for the Casements of the Kelley or Kella , I have also researched back to Thomas, late 1600,s and his father was possibly another Thomas. I know nothing about these Thomas' although I am beginning to feel that any links between the different Casement families may be even further back in time.

Thanks again, Elizabeth.