NOW YOU KNOW

• On May 2, 1941,  General Mills began shipping its new cereal, "Cheerioats," to six test markets.  (The ceral was later renamed "Cheerios.")
• On May 3, 1911,  Wisconsin Gov. Francis E. McGovern signed the first U.S. workers' compensation law to withstand constitutional scrutiny.  (Previous attempts in Maryland, Massachusetts, Montana and New York were struck down.)
• On May 4, 1961,  the first group of "Freedom Riders" left Washington, D.C., to challenge racial segregation on interstate buses and in bus terminals.  The Freedom Riders were repeatedly attacked by violent mobs, mostly in Alabama.
• On May 6, 1889,  the Paris Exposition formally opened, featuring the just-completed Eiffel Tower.
• On May 9, 1914,  President Woodrow Wilson issued a proclamation asking Americans to give a public expression of reverence to mothers through the celebration of Mother's Day.
• On May 10, 1869,  a golden spike was driven in Promontory, Utah, marking the completion of the first transcontinental railroad in the United States.
• On May 11, 1811,  conjoined twins Chang and Eng Bunker were born in Siam (now Thailand), giving rise to the term "Siamese twins."
• On May 12, 1932,  the body of Charles Lindbergh Jr., the kidnapped son of Charles and Anne Lindbergh, was found in a wooded area near Hopewell, N.J.
• On May 13, 1861,  Britain's Queen Victoria declared her country's neutrality in the American Civil War, but also acknowledged that the Confederacy had belligerent rights.
• On May 16, 1939,  the government began its first food stamp program in Rochester, N.Y.
• On May 17, 1792,  the New York Stok Exchange had its origins as a group of brokers met under a tree on Wall Street.
• On May 18, 1980,  the Mount St. Helens volcano in Washington state exploded, leaving 57 people dead or missing.
• On May 19, 1967,  the Soviet Union ratified a treaty with the United States and Britain banning nuclear and other weapons from outer space as well as celestial bodies such as the moon.
• On May 23, 1934,  bank robbers Clyde Barrow and Bonnie Parker were shot to death in a police ambush in Bienville Parish, La.
• On May 24, 1844,  Samuel F.B. Morse transmitted the message, "What hath God wrought" from Washington to Baltimore as he formally opened America's first telegraph line.
• On May 25, 1787,  the Constitutional Convention began meeting in Philadelphia after enough delegates had shown up for a quorum.
• On May 26, 1940,  the evacuation of more than 338,000 Allied troops from Dunkirk, France, began during World War 2.
• On May 27, 1896,  255 people were killed when a tornado struck St. Louis, Ill.
• On May 31, 1911,  the hull of the British liner RMS Titanic was launched from its building berth at the Port of Belfast, less than a year before the ship's fateful maiden voyage.