This treasure appeared in facebook transportdownunder.  David has given me approval to repost here.
Roderick.

David Critchley: A Postcard in my collection. A Bon Marche printed postcard. Mint.
Fremantle c1905. From what I have researched, the paddle tug 'Nirimba' was built by W & S Lawrence in Perth during 1895 for the Swan River Shipping Co. Ltd.  Launched by Lady Forrest, Nirimba had an overall length of 92ft, a beam of 17ft 3in and a depth of hold of 5ft 9in. Her draught was a shallow 2ft 6in.  The vessel was used as a tug around the port of Fremantle and would have also ventured up Swan River. Unfortunately, there is no details about its steam engine. It was scuttled off Rottnest island in 1945.