Canals - The Tavistock Canal
One of the jewels in the engineering crown of the Tamar Valley mining district, the Tavistock Canal was conceived around 1800 by mining and other entrepreneurs in West Devon, primarily as a means of cheaply transporting the produce of local mines out of the district, for smelting.
See route map.
It was quickly realised that the back-carriage of such cargoes as coal and limestone would realise a substantial trade, developing industry in Tavistock and improving the surrounding land. To this end, the Mount Foundry commenced construction in Tavistock in 1800 and was operational by 1804, while several other industries expanded.
A tertiary consideration was the exploration and development of hitherto unseen potential deposits of metalliferous ores under Morwell Down, an area known to be rich in tin and copper. To this end, a long tunnel of 1½ miles was planned to pierce the Down, passing through at least four known lodes and arriving at a height of 237 feet above the Tamar. Bringing the cargoes down this hill was a secondary consideration to the amount of power available from the canal water. The canal was designed to flow, and at least 35 water wheels were driven by it at various times in its life; the canal company owning and operating several mines along its course.
The driving force behind the canal was almost certainly its engineer, John Taylor, who was only 24 at the time of its commencement in 1803. Taylor had begun his career as manager of Wheal Friendship tin mine near Mary Tavy in 1798, at a time when this mine was losing money due to ill-management. He turned it round within four years through a combination of good financial management and investment in water power. This was to serve him in good stead for the remainder of his long working career, which saw him profit from such techniques in many parts of Britain and even abroad.
The canal was commenced in 1803, but due to the hardness of rock encountered in tunnelling through Morwell Down, was not completed until 1817. It was not a spectacular success as a waterway, partly owing to financial hardships after the Napoleonic Wars, meaning that parts of it were under-used; and partly to costing considerably more than its construction budget. It was of considerably more use as a power source; its water still being used for mining purposes as late as 1930. Its subsequent use from 1933 to drive a hydro-electric power station has kept it in use for one of its primary design uses up to the present day - a proud achievement.
Detailed archaeological surveys and excavations along the course of the canal commenced in 2003, with the intention to produce a book on the canal's archaeology. This work was completed in 2010, and selected examples of surveys are presented on this website,
(see Archaeological Surveys & Excavations page).
Several pioneering devices and engineering solutions were associated with the canal. These included the use of mechanical air pumps for ventilating mines (1808), wrought iron canal boats (from 1811), the use of underground inclined planes to reduce costs associated with ore handling (1812), and containerisation (from 1816). During construction, flatrods totalling 1½ miles crossed Morwell Down to pump the four tunnel development shafts and were the longest continuous run of such rods to be seen in the region. At the date of opening, the Morwell Down Tunnel was the longest canal tunnel in Britain at 5040 yards and the Morwellham Inclined Plane was the longest in the region (720 feet).