In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Middleton on Sea like this:
MIDDLETON, a parish in Westhampnett district, Sussex; on the coast, 2½ miles E of Bognor r. station. It includes the hamlet of Elmer; and its Post town is Bognor. Acres, 859; of which 213 are submerged every tide. Real property, £665. Pop., 89. Houses, 16. The property is divided among a few. Much land has been removed by encroachment of the sea. The living is a rectory in the diocese of Chichester. Value, £180. Patron, George H. Roe, Esq. The old church was swept away by the sea; and the present church was built in 1849.
GB Historical GIS / University of Portsmouth, History of Middleton on Sea, in Arun and Sussex | Map and description, A Vision of Britain through Time.
Date accessed: 25th March 2017
Click here for more detailed advice on finding places within A Vision of Britain through Time , and maybe some references to other places called " Middleton on Sea ".