SS Cushag was sold once more, this time to a London broker, from whom she was purchased by the Isle of Man Steam Packet Company in May 1920, at a cost of £22,000 (equivalent to £). Small and drawing so little water, she was mostly used for cargo trade in the Island's smaller ports - Port St Mary, Peel, Laxey and Castletown. After over 20 years service with the Company, she was sold to London agents in January 1943, and then went on to Stornoway on the Isle of Lewis for four years. She transferred to Kirkwall in Orkney in 1947. "Cushag"
Castletown, Isle of Man to the west Port St Mary and Port Erin. The older parts of the town are largely built of local grey limestone. At Scarlett, a short distance to the south of the town, there are the remains of an ancient volcano and various other features such as fossils and thick sheets of limestone. The A3 road connects Castletown with Ramsey via St John's, while the A5 road (also known as New Castletown Road as opposed to the Old Castletown Road which takes a more rural route nearer the coast) connects the town with Douglas to the north-east and Port Erin