MODEL IS SOLD.
This invention had “a concave bottom in semicircular form” atop the bottom is a zinc or tin “washboard”. The clothes are laid on that board and rubbed back and forth by semicircular heads…..That cleaned the clothes!
Of course more critical explanations are in the inventors claim about pivots, vertical grooves, endboard and crossbars. A very well made all wood model that would display very nicely in any collection.