English: Mooring bitts on board SS Shieldhall. SS Shieldhall is a preserved steamship that operates from Southampton. She spent her working life as one of the "Clyde sludge boats", making regular trips from Shieldhall in Glasgow, Scotland, down the River Clyde and Firth of Clyde past the Isle of Arran, to dump treated sewage sludge at sea. These steamships had a tradition, dating back to World War I, of taking organised parties of passengers on their trips during the summer. SS Shieldhall has been preserved and the accommodation is again being put to good use for cruises.