At first blush, the idea of a washing machine powered by a small gasoline engine seems a bit wacky. But in the first half of the 20th century, electricity was not always available, particularly in rural areas. The gas engine was adapted to power many labor saving devices, easing the burden of farm and household chores.
This machine was probably demonstrated during my visit to Somerset, but I missed seeing it in action. The video below shows a similar machine running.