than 1200 at Jallianwala Bagh in Amritsar, Punjab Province (British India). May – Third Anglo-Afghan War begins. 15 May – Greek landing at Smyrna (as part of the Greco-Turkish War): The Hellenic Army lands at Smyrna assisted by ships of the British Royal Navy. 12 May – the Pip, Squeak and Wilfred comic strip debuts in the Daily Mirror. 29 May – observations made by Arthur Eddington during a solar eclipse test part of Einstein's general theory of relativity (confirmed 6 November). June – riots break out in west midlands towns. 14–15 June – a Vickers Vimy piloted by John Alcock DSC with navigator Arthur Whitten Brown makes the first nonstop transatlantic flight, from St. John's, Newfoundland and Labrador, to Clifden, Connemara, Ireland. 17 June – Epsom Riot by Canadian troops: English police sergeant Thomas Green is killed. 21 June – Scuttling of the German fleet in Scapa Flow: Admiral Ludwig von Reuter scuttles the interned German fleet in Scapa Flow, Scotland. Nine German sailors are killed. 23 June – Women's Engineering Society founded. 28 June – Treaty of Versailles signed, formally ending World War I. 2–6 July – the British airship R34 makes the first transatlantic flight by dirigible, and the first westbound flight, from RAF East Fortune, Scotland, to Mineola, New York. 15 July – naval sloops HMS Gentian and HMS Myrtle sunk by mines in the Gulf of Finland while assisting Estonia against the Bolsheviks, with nine crew lost. 18 July – the Cenotaph in London, as designed by Edwin Lutyens, is unveiled to commemorate the dead of World War I. 19 July – Peace Day: victory parades across Britain celebrate the end of World War I. Rioting ex-servicemen burn down Luton Town Hall. 31 July Police strike in London and Liverpool for recognition of the National Union of Police and Prison Officers. Rioting breaks out in Liverpool on 1 August. Over 2,000 strikers are dismissed. Housing, Town Planning, &c. Act 1919 provides government subsidy for the provision of council houses, with the target of completing 500,000 houses by 1922. 8 August – the Anglo-Afghan Treaty of 1919, signed in Rawalpindi, ends the Third Anglo-Afghan War, with the UK recognising the right of the Emirate of Afghanistan to manage its own foreign affairs and Afghanistan recognising the Durand Line as the border with British India. 9 August – the Anglo-Persian Agreement, signed in Tehran, grants the UK