In The Antipodean cookery book and kitchen companion (1897) she gives detailed instructions on washing up which involved boiling water in a cut down kerosene tin, which could also accommodate pots, pans and plates, and building a wooden rack which would fit over the wash tub on which soiled dishes and pans could be placed and hot soap suds poured over them. She also advocated a scrubbing brush with a long handle and 'a chain pot-cleaner' which could be fixed on to a handle so that 'the hands need not even be soiled'.
It should not be a surprise then that she invented, and applied for a patent for, an 'Improved labour saving kitchen utensil to be called Mrs Lance Rawson's Kitchen Help'. The Patent's Office were unclear as to whether it was a washing machine, a cooking utensil or a vegetable cleaner but from her description it is clearly intended to be a machine for washing, albeit for smallish 'articles'.
You can see the original patent application, dated 26 September 1898, by searching on the National Archives of Australia web site here.
This is how Mina describes here invention:
My invention is composed of a galvanised iron vessel or billy with a strainer inside revolving on a pivot and connected by a handle from the outside lid. The vessels are of two sizes fifteen inches and two feet in diameter. The outside vessel has hand rests on each side with three rests inside for the strainer to stand on and an overflow to discharge all water after use. The inside strainer is also of galvanised iron and revolves on a pivot fixed to the bottom of the outside vessel and is worked by a handle from the top. The articles that require cleaning are put in the inside strainer and by turning the handle on the top of the outside vessel enables the boiling water to pass through and over the articles and cleans them without any handling.She omits to mention that presumably the water has to be fed into the machine somehow and doesn't specify what 'articles' she has in mind to be cleaned. Washing crockery in this apparatus would seem a hazardous business and the inner drum, with a diameter of 38 cm, would only be large enough for small pans, cooking utensils and cutlery. There is no specification for the height of the vessels but if the drawings are to scale the outer vessel stood at around 61 cm with a diameter roughly the same, which means the contraption would take up a fair bit of room in the kitchen.
No doubt Mina had some sort of prototype made but just how effective this gadget was we may never know. I could find no evidence that this idea went any further than the Patents Office. The record states that the patent was not registered. The Brisbane Courier, 10 October 1898, notes only that the registrar of patents did accept the application. However there is an intriguing reference in The Queenslander (10 June 1899). A reply to correspondence received reads 'If you mean a washing-up machine write to Mrs Lance Rawson, Rockhampton who is the inventor' which suggests that the idea may have progressed beyond the drawing board.