In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Clack like this:
CLACK, a chapelry in Lyneham parish, Wilts; near the Great Western railway, 5 miles SW of Wootton-Bassett. Pop., 370. Fairs are held on 5 April and 10 Oct. Clack hill has ancient earthworks. The living is a p. curacy. Value, £110. The church was built in 1866.
Additional information about this locality is available for Lyneham
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 Clack has changed, please see our redistricted information for the modern district of North Wiltshire. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Clack and units named after it.
GB Historical GIS / University of Portsmouth, History of Clack in North Wiltshire | Map and description, A Vision of Britain through Time.
Date accessed: 21st May 2013
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