In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Mappowder like this:
MAPPOWDER, a parish in Dorchester district, Dorset; 6 miles NE by E of Cerne-Abbas, and 6 SW of Sturminster-Newton r. station. Post town, Blandford. Acres, 1,887. Real property, £2,538. Pop., 238. Houses, 48. The property is chiefly in one estate. Stone is quarried. The parish is a meet for the Blackmoor Vale harriers. ...
The living is a rectory in the diocese of Salisbury. Value, £390. Patron, G. D. W. Digby, Esq. The church is a fine edifice, with a tower; was about to be restored in the summer of 1867; and contains a Norman font, an effigies of a crusader, and monuments of the Cokers. John Coker, author of the "Survey of Dorset, ''was a native.
GB Historical GIS / University of Portsmouth, History of Mappowder in North Dorset | Map and description, A Vision of Britain through Time.
Date accessed: 27th 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 " Mappowder ".