Edge Trimming and Mowing Machine
However, a design of Joesphus Miller of Louisville, Kentucky, USA, pre-dates the Rotoscythe. The machine was sold by the Louisville Electric Manufacturing Co under the name Pioneer. US patent 1,831,681 was applied for by Miller on 19th October 1928 and granted on 10th November 1931. The machine featured a horizontal cutting blade directly connected to a vertically mounted electric motor. The height of cut of the described lawnmower was adjusted by moving the entire motor/blade assembly up or down as required.
The blade was described as being either a single one sharpened at its "diametrically opposed" ends as in many modern rotaries, or as a transverse bar to whose extremities cutting blades or circular cutting disks were attached. The mower seems to have cut (and at least one example apparently still cuts) grass adequately.