The Idrija kamšt, a water wheel 13.6 metres in diameter, was used to pump pit water out of the shafts of the Idrija Mercury Mine. Kamšt derives from the German word Wasserkunst and was erected 1790 in the years of prosperity and development when Francis's Shaft was sunk. A state of the art technical achievement at the time when it was made, Idrija kamšt is today is believed to be the largest preserved water wheel of this kind in Europe. The flood dams which powered it were built in the hills 3.5 km above the kamšt, from where water was driven through a channel called a rake. The water-driven wheel made 4-5 turns a minute and pumped 300 litres of pit water per minute from a depth of 283 metres below the surface. The rotation of the driving wheel was transmitted by a 75-metre-long system of handles, rods, and poles. The same dams and rake that powered the kamšt today power the hydro power plant in Idrija.