Joseph Day (inventor)
Joseph Day (1855 – 1946) is a little-known English engineer who developed the extremely widely used crankcase-compression two-stroke petrol engine, as used for small engines from lawnmowers to mopeds and small motorcycles. He trained as an engineer at the Crystal Palace School of Engineering at Crystal Palace in London, began work at Stothert & Pitt in Bath, and in 1889 designed the crankcase-compression two-stroke engine as it is widely known today (in contrast to the two-stroke engine designed by Dugald Clerk), the Valve-less Two-Stroke Engine.