Abstract: An apparatus for transporting and retaining payloads on ferrous metal surfaces, using at least one electromagnet, obviating the need for electric wiring from a ship by utilizing an electricity supply facility which is disposed on the apparatus, such supply facility preferably being a compressed-air motor and D.C. generator.

Abstract: A device for cleaning surfaces which extend in a vertical plane and particularly ship's sides, tank walls and similar surfaces which are made of ferromagnetic material, comprises a lifting mechanism which has roller means permitting it to run along a ship's railing or similar structure adjacent the top of the surface to be cleaned. The lifting mechanism includes one or more winding drums or hoists which carry support line means which extend from the lifting mechanism to a carrier for a cleaning apparatus. The cleaning apparatus advantageously includes a housing having an undercarriage which is movable along the surface to be cleaned and which includes magnetic means for causing an attraction between the carrier and the surface to be cleaned so that the carrier is held thereagainst during the cleaning operation.