A nice reconstruction of an elaborate double bucket pot with windmill-driven pump is provided for a site in Fife in the following source: Yeoman, P. (ed.) (1999) Salt and coal industries at St Monans, Fife in the 18th and 19th centuries. Tayside and Fife Archaeological Committee, Monograph 2. Glenrothies. Although never as sophisticated as these, the Ballycastle sites worked basically in the same way.