SS Cadmus was a cargo ship of 1,879 GRT built in 1911 by Shipbuilding & Drydock Co. Ltd., West Hartlepool, for John Gaff & Co., of Glasgow and Sydney.
On 18 October 1917, she was on her way from Dunkirk to Blythe with a cargo of 900 tons of spent cartridge cases from 18-pounder guns for recycling.
SM UC-47 torpedoed and sank her in the North Sea 20 nautical miles (37 km) south by east of Flamborough Head (53°50′55″N 00°12′27″E / 53.84861°N 0.20750°E / 53.84861; 0.20750).
[3] Cadmus, of 1,855 GRT, was launched in 1926 by Kjøbenhavns Flydedok & Skibsværft, Copenhagen, and was owned by L. Harboe Jensen & Co, Oslo.
She was sailing from Tela, Honduras to Galveston with a cargo of bananas, when on 1 July 1942, the German submarine U-129 torpedoed her at 22°50′N 92°30′W / 22.833°N 92.500°W / 22.833; -92.500.
Twenty crew members survived in two boats and five days later landed near Texpan, Mexico.