The Fall of Foyers is a waterfall

Waterfall

A waterfall is a place where flowing water rapidly drops in elevation as it flows over a steep region or a cliff.-Formation:Waterfalls are commonly formed when a river is young. At these times the channel is often narrow and deep. When the river courses over resistant bedrock, erosion happens...

 on the River Foyers, which feeds Loch Ness

Loch Ness

Loch Ness is a large, deep, freshwater loch in the Scottish Highlands extending for approximately southwest of Inverness. Its surface is above sea level. Loch Ness is best known for the alleged sightings of the cryptozoological Loch Ness Monster, also known affectionately as "Nessie"...

, in Highland

Highland (council area)

Highland is a council area in the Scottish Highlands and is the largest local government area in both Scotland and the United Kingdom as a whole. It shares borders with the council areas of Moray, Aberdeenshire, Perth and Kinross, and Argyll and Bute. Their councils, and those of Angus and...

, Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

, United Kingdom

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

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The waterfall has "a fine cascade", having a fall of 165 feet. It is located on the lower portion of the River Foyers at . The river enters Loch Ness on the East side, North-East of Fort Augustus

Fort Augustus

Fort Augustus is a settlement in the Scottish Highlands, at the south west end of Loch Ness. The village has a population of around 646 ; its economy is heavily reliant on tourism....

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This waterfall influenced Robert Addams to write a paper in 1834 about the motion aftereffect

Motion aftereffect

The motion after-effect is a visual illusion experienced after viewing a moving visual stimulus for a time with stationary eyes, and then fixating a stationary stimulus. The stationary stimulus appears to move in the opposite direction to the original stimulus...

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The flow over the falls has been much reduced since 1895 when North British Aluminium Company

British Aluminium

The aluminium producer British Aluminium Ltd was originally formed as the British Aluminium Company Ltd on 7 May 1894 and was subsequently known as British Alcan Aluminium Plc...

 built an aluminium

Aluminium

Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....

 smelting

Smelting

Smelting is a form of extractive metallurgy; its main use is to produce a metal from its ore. This includes iron extraction from iron ore, and copper extraction and other base metals from their ores...

 plant on the shore of Loch Ness which was powered by electricity generated by the river. The plant shut in 1967 and the site is now part of a Pumped-storage hydroelectricity

Pumped-storage hydroelectricity

Pumped-storage hydroelectricity is a type of hydroelectric power generation used by some power plants for load balancing. The method stores energy in the form of water, pumped from a lower elevation reservoir to a higher elevation. Low-cost off-peak electric power is used to run the pumps...

system.