The family are mis-transcribed as Derdrap on the 1841, They are living on "Crowthorn" - the same as in 1851. Ref HO107/532/1folio 10,page 12.
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James Dewsnap married Mary Hallows 2nd May 1825, The children were christened at St Mary's Independant, Glossop batch number: C066721. Elizabeth is down as "Deusnap" born 23 April 1830 christened 20 June 1830.