Events January–March January 21 – José Mariano Salas (1797–1867) becomes Conservative interim President of Mexico. January 24 (O. S.) – Wallachia and Moldavia are united under Alexandru Ioan Cuza (Romania since 1866, final unification takes place on December 1, 1918; Transylvania and other regions are still missing at that time). January 28 – The city of Olympia is incorporated in the Washington Territory of the United States of America. February 2 – Miguel Miramón (1832–1867) becomes Conservative interim President of Mexico. February 4 – German scholar Constantin von Tischendorf rediscovers the Codex Sinaiticus, a 4th-century uncial manuscript of the Greek Bible, in Saint Catherine's Monastery on the foot of Mount Sinai, in the Khedivate of Egypt. February 14 – Oregon is admitted as the 33rd U.S. state. February 12 – The Mekteb-i Mülkiye School is founded in the Ottoman Empire. February 17 – French naval forces under Charles Rigault de Genouilly capture the city and Citadel of Saigon in Vietnam, beginning the Siege of Saigon. February 27 – United States Congressman Daniel Sickles shoots Philip Barton Key (U.S. District Attorney) for having an affair with his wife. March 3 – Construction begins on the first railway in northern India as tracks are laid between the modern-day locations of Allahabad and Kanpur. March 9 – The army of the Kingdom of Sardinia mobilizes against Austria, beginning the crisis which will lead to the Austro-Sardinian War. March 21 – The Commonwealth of Pennsylvania issues the charter establishing the Zoological Society of Philadelphia, the first organization of its kind in the United States, and founder of the nation's first zoo. March 26 – French amateur astronomer Edmond Modeste Lescarbault claims to have noticed a planet closer to the Sun than Mercury (later named Vulcan). April–June April 13 – The Cooper Union for the Advancement of Science and Art is founded by Peter Cooper, a New York industrialist, inventor and philanthropist. April 18 – Indian Rebellion revolutionary, Tantia Tope is hanged for the 1857 Rebellion April 25 – Ground is broken for the Suez Canal, in Egypt. April 28 – American ship Pomona is wrecked off the Irish coast, with 424 dead. April 29 – Austrian troops begin to cross the Ticino River to Piedmont. April 30 – A Tale of Two Cities by Charles Dickens is published in England. May 4 – The Cornwall Railway opens across the Royal Albert Bridge, linking the