Hi Clive,

Why the "??"? The Maughold parish register has the marriage as:
9 Feb 1850
John KINRADE Full age Bachelor Shoemaker Kirk Andreas, [father] John Kinrade, Labourer, and
Mary Ann MASTYN Full age Spinster Thalloo Queen, [father] Joseph Mastyn, Labourer.

The name was clearly MASTYN, and there were many Mastin/Mastyn families in England (see the IGI), as distinct from Marsden.
- Also many in Scotland, and a few in Ireland.

Sue