Watching brief by R Savage of SyAS during a stoppage on the Wey Navigation. Evidence for the construction of a partition or weir between the large mill pond and the Navigation was revealed. The brick and timber construction of the weir incorporated rectangular blocks of waste from copper processing and may date from Alexander Raby’s ownership of the site between c 1777 and 1807 when he maintained an iron and copper works here. Metalworking continued at the adjacent mill until 1831, so the construction of the weir could relate to later works.