I have just found this marriage on the new familysearch!
Peter Musselwhite married Sophia Benfield at Plumstead, Kent, on 23 July 1807.
I was surprised as their daughter Charlotte was born in Swanage in 1808 so assumed they must have married in Dorset.
I have also now found the baptism of their daughter Caroline (incorrectly in the register as Burdon [Peter's mother's maiden name - perhaps his middle name] with 'Michel White' as a middle name) in Woolwich in 1816.
This shows Peter was a Stone Mason.
Regards,
Jon