Leonard H. Dyer (1897–1955) was an inventor, patent attorney, and yachtsman from Washington, DC.
The most remarkable of his inventions was a patented six stroke engine using water injected as a 5th stroke for extra power and cooling, to be ejected on the final (sixth) exhaust stroke. Though this patent does not have an extensive past, it came up in 2008 with regards to the Crower six stroke engine.
Mr. Dyer was a member of somewhat high society, with a net worth of at least $500,000 in 1922. He owned the Yacht "Jack 'O Lantern," which was piloted to several victories by Abbot H. Brush.
Despite his high ties, there was trouble at home. In late 1922, a petition for divorce was filed by his wife, Josephine Dryer in Greenwich, Connecticut, citing intolerable cruelty, and infidelity with a young woman from Greenwich.