London. May 17 – U.S. Army aviation pioneer Major Harold Geiger dies in the crash of his Airco DH.4 airplane, at Olmsted Field, Pennsylvania. May 18 – Bath School disaster: A series of violent attacks by a school official results in 45 deaths, mostly of children, in Bath Township, Michigan, United States. May 20 – By the Treaty of Jeddah, the United Kingdom recognizes the sovereignty of Ibn Saud over the Kingdom of Hejaz and Nejd, the future Saudi Arabia. May 20–21– Charles Lindbergh makes the first solo, nonstop transatlantic airplane flight, from New York City to Paris, France, in his single-engined aircraft, the Spirit of St. Louis. May 22 – The 7.6 Gulang earthquake affects Gansu in northwest China with a maximum Mercalli intensity of XI (Extreme), leaving over 40,000 dead. May 23 – Nearly 600 members of the American Institute of Electrical Engineers and the Institute of Radio Engineers view a live demonstration of television at the Bell Telephone Building in New York City, just over a year after John Logie Baird of Scotland had first demonstrated an electromechanical system to members of the Royal Society in London. May 24 – The United Kingdom cuts its diplomatic relations with the Soviet Union due to revelations of espionage and underground agitation. June June – The volcanic island of Anak Krakatau begins to form in the Sunda Strait of Indonesia. June 4 – Yugoslavia severs diplomatic relations with Albania. June 4–6 – Clarence Chamberlin and Charles Albert Levine take off from Roosevelt Field, New York, and fly to Eisleben, Germany, in the Wright-Bellanca WB-2 Columbia aircraft Miss Columbia, two weeks after Charles Lindbergh's historic solo flight. June 9 – The Soviet Union executes 20 people for alleged espionage in retaliation for the assassination two days earlier of Pyotr Voykov, the Soviet ambassador to Poland, at the railway station in Warsaw. Voykov had been shot by 19-year-old Boris Kowerda, an exiled Russian, in retaliation for having signed the death warrants in 1918 for Tsar Nicholas II and the Russian Imperial Family. June 13 Léon Daudet, the leader of the French monarchists, is arrested in France. A ticker tape parade is held for aviator Charles Lindbergh down Fifth Avenue in New York City. June 18 – The Association football club Persebaya Surabaya is founded in the Dutch East Indies (modern-day Indonesia). June 28 – Spanish airline Iberia is established. June 29 –