Wigan's status as a centre for coal production, engineering and textiles in the 18th century led to the Douglas Navigation in the 1740s, the canalisation of part of the River Douglas, and later the diversion of the Leeds and Liverpool Canal in the 1790s at the request of the mill owners, to transport coal from the Lancashire coal pits to Wigan's mills and was also used extensively to transport local produce. As a mill town, Wigan was an important centre of textile manufacture during the Industrial Revolution; however it wasn't until the 1800s that cotton factories began to spread into the town. This was due to a dearth of fast-flowing streams and rivers in the area, but by 1818 there were eight cotton mills in the Wallgate part of Wigan. In 1818 William Woods introduced the first power looms to the Wigan cotton mills.