In the 19th century St. Thomas-the-Apostle was a parish within Launceston Poor Law Union and Registration District.
A Vision of Britain through Time provides the following description of St. Thomas the Apostle from John Marius Wilson's Imperial Gazetteer of England and Wales of 1870-72:
In 1889 the parish of St. Thomas the Apostle was split into two sections: St. Thomas the Apostle Urban and St. Thomas the Apostle Rural. In 1894 was absorbed into Launceston Municipal Borough, and St. Thomas-the-Apostle Rural Civil Parish joining the Launceston Rural District. In the 1891 census the population was given as 352 (urban) and 924 (rural).
One of the many maps available on A Vision of Britain through Time is one from the Ordnance Survey Series of 1900 illustrating the parish boundaries of Cornwall at the turn of the 20th century. This map blows up to show all the parishes and many of the small villages and hamlets.
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