In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Witherstone like this:
WITHERSTONE, a tything in Poorstock parish, Dorset; 5 miles ENE of Bridport. Pop., 41. It ranks as a sinecure rectory in the diocese of Salisbury. Value, £94. Patron, the Earl of Dorchester.
A Vision of Britain through Time includes a large library of local statistics for administrative units. For the best overall sense of how the area containing Witherstone has changed, please see our redistricted information for the modern district of West Dorset. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Witherstone and units named after it.
GB Historical GIS / University of Portsmouth, History of Witherstone in West Dorset | Map and description, A Vision of Britain through Time.
Date accessed: 27th April 2015
Click here for more detailed advice on finding places within A Vision of Britain through Time, and maybe some references to other places called "Witherstone".