There is a fascinating copy of the Hatherleigh Tithe Map of 1839 available online at the Devon County Council Historic Environment website: https://www.devon.gov.uk/historicenvironment/tithe-map/hatherleigh/
This is a high resolution digital scan of the original map and can be zoomed and scrolled, and is accompanied by a transcription of the tithe apportionment or reference book. This gives details of the owner, occupier and property type or cultivation use for every property and plot in the parish, which are all numbered on the map.
Historically, payment of tithes was made to the rector of the parish and generally paid in kind. The 1836 Commutation of Tithes Act set out to commute these payments to cash, to which end surveys were carried out across the whole of England and Wales. Over the course of the following decade tithe maps were created for virtually every parish to assess the amount of tithe payable for each parcel of land, and apportionment made. This was payable in cash to the parish church for the support of the church and its clergy.
Hatherleigh’s own copy of the original tithe map, thought lost for a number of years, was discovered again in Old Schools in 1998 and is now deposited at the South West Heritage Centre in Exeter.