The fastest of Melbourne's many paddlesteamers for the bay-excursion trade was PS Hygiea. According to Fitchett ('Down the bay' Rigby 1973) it had a speed of 21 knots [38 km/h]. This family of bay-cruising paddlesteamers was based on the style used on Clyde River (Glasgow, Scotland). I guess that there many paddlesteamers there capable of achieving this speed.
Loney ('Bay steamers and coastal ferries') reported two races of rival ferries PS Ozone and SS Courier (both capable of ~18 knots, 33 km/h). Essentially, the paddle company slipped its boat and polished the hull, then loaded it with just sufficient coal to reach Portarlington, carried just a few specially-invited guests, and lay in wait for the screw rival, fully laden, on a regular run. Despite being caught on the hop, the skipper of the latter put up a good fight. The paddlesteamer won, but not by a huge margin. The company promptly forbade its captains from racing.
Neverthless, the screw company did mount a rematch. The paddlesteamer raced briefly, then pulled back. Then it set forth again with gusto: the judgement is equivocal. Did it just hold the distance, or did it regain? In any case, the later Hygiea eclipsed both for speed.
I noticed in April how sprightly the Swiss lake paddlesteamers were: and we may not even have been cruising at full speed.
Regards,
Roderick B Smith
Rail News Victoria Editor