The William Yates (c.1737-1802) survey of the county of Warwickshire was the most important published since that of Henry Beighton in 1729. It was surveyed at the scale of one inch to the mile with the assistance of his two sons. To achieve this work two base lines of about 10 miles each were measured and from these a network of triangulation was made. The grid for this is included in the map. The sites of these two lines were decided upon because of good visibility. One is taken from the excellent view points of the spire of St, Michael’s in Coventry to St. Mary’s Church Tower in Warwick. The other runs along a section of the old Roman road Watling Street. The further points in the triangulation are all points of good visibility such as churches and windmills. This gave the map a degree of accuracy recognised by the Society of Arts who gave it an award.

In his eagerness to be accurate and up-to-date he made a point of finding out as much as he could about the rapidly expanding canal network. This unfortunately encouraged him to not only apply the routes of canals not yet built but also those of ones not yet approved. The Birmingham-Warwick canal was not finally in use until 1799 and the Stratford-on-Avon canal was just a proposition and not completed until 1816. The extensions from Hockley to Tamworth and Hardwick to Binton were never constructed. One of the most fascinating parts of the map is seeing the open spaces between Birmingham and the nearby towns of Edgbaston, Aston, Moseley, Handsworth and Yardley. A vision of how land would be eaten up by the rapid industrialisation in the ensuing two hundred years. The survey did not end at the county border extending to take in the nearby towns in some detail. The Explanation helps to identify the Market Towns, Seats, Churches, Turnpike Roads noting Milestones and ‘Toll Barrs’, Rivers complete with Water Mills, Canals with locks and bridges, coal pits and political boundaries. An ornate compass appears upper left and a fine vignette of St. Mary’s Church Tower in Warwick. Upper right is a plan of the measurements taken to triangulate the county. The map was published by John Sharp, a bookseller in the High Street, Warwick. Large scale surveys by Yates are rare, he only produced two others; Staffordshire 1775 and Lancashire in 1786. Prior to that he worked with his then partner John Chapman in a survey of Derbyshire for Peter Perez Burdett, published c.1767. He was a surveyor and Customs Officer at Liverpool from 1771-1802. Delano-Smith & Kain (1999) pp. 88-91, 94-5; France, R. Sharpe (1958) ‘William Yates, Cartographer’, in ‘Transactions of the Lancashire and Cheshire Historic Society’ Vol. 109 pp. 200-02; Harvey & Thorpe (1959) no. 51 & pp. 39-41; Imago Mundi 19 pp. 56 & 63; Rodger (1972) 479; Tooley’s Dictionary.