In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described St Erney like this:
ERNEY (St.), a parish in St. Germans district, Cornwall; on Lynher creek, 3¼ miles W of Saltash. Pop., 79. Houses, 13. It is joined to Landrake: which see.
Additional information about this locality is available for Landrake
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 St Erney has changed, please see our redistricted information for the modern district of Caradon. More detailed statistical data are available under Units and statistics, which includes both administrative units covering St Erney and units named after it.
GB Historical GIS / University of Portsmouth, History of St Erney, in Caradon and Cornwall | Map and description, A Vision of Britain through Time.
Date accessed: 08th February 2016
Click here for more detailed advice on finding places within A Vision of Britain through Time, and maybe some references to other places called "St Erney".