Driven by the flow of the river this had scoops on the back of the blades which raised a small proportion of the flowing water into the higher canal. This was completed in 1787. A second artificial cut was added in 1790 from Coldwaltham to Stopham, including a 375-yard (343 m) tunnel under Hardham Hill, which avoided a large bend in the river near Pulborough, saving . The route of the Navigation from Newbridge to Houghton was with six locks. The river continues a further to the sea at Littlehampton. The last barge to travel on the section between Pallingham and Newbridge was recorded in 1888, and Hardham tunnel was closed in 1889. The artificial cuts were officially abandoned in 1896, but limited traffic continued on the old river sections into the 20th century, notably bricks from Harwoods Green below Pallingham and chalk from Houghton Bridge; they were finally stopped in 1938 by a new, fixed bridge on the Havant to Brighton railway line at Ford. The first scheme to link the Wey and the Arun was proposed in 1641. Tributaries of both rivers were only apart, and a canal to bridge this distance was submitted as a bill to Parliament, but was dropped when it reached the committee stage. Another scheme, which would have linked up the rivers Adur, Arun, Mole and Wey, was suggested in 1663, but was not pursued. In 1810, the 3rd Earl of Egremont began to promote the idea of a canal to link the Rivers Wey and Arun, separated by only 15 miles (24 km). Part of the justification for this canal through a very rural area, with few of the cargoes which had made other canals profitable, was to provide an inland route from London to Portsmouth and the south coast of England, an important consideration as England was at war with France and thus coastal shipping at risk of attack. Josias Jessop (son of the more well known William Jessop) was appointed consulting engineer in 1811. It was his first job as an independent consulting engineer since he had established his reputation constructing Bristol Harbour. He made an estimate of £72,217 for construction of the canal, which he increased to £86,132 in May 1812, when he re-surveyed the route and part of it was changed. A survey was carried out in 1811 by Francis and Netlam Giles for an alternative route, long, from the Croydon, Mersham and Godstone Railway at Merstham to Newbridge, via Three Bridges, Crawley and Horsham.