After the First World War she was converted into a passenger ferry, serving first the Isles of Scilly as Peninnis and then in the Channel Islands as Riduna.

Bow, McLachlan and Company built Argus in Paisley, Renfrewshire, launching her on 6 December 1904 and completing her in 1905.

She had a single screw, driven by a three-cylinder Triple expansion engine that was rated at 65 NHP and age her a speed of 11+1⁄2 knots (21.3 km/h).

[2] In July 1909 she was off Hastings, under the command of Captain Hicks RN, watching the interests of British fishermen and keeping a look out for French boats within the three mile radius.

Ward sold her on to the Isles of Scilly Steamship Company for £8,000,[1][a] refitted for £5,000 and renamed RMS Peninnis.