"Eight Hours for work. Eight hours for rest. Eight hours for what we will." In 1886, the average American workweek was 60 hours over 6 days. On May 1 of that year, as many as half a million workers march in support of the 8 hour work day. Two days later, at a rally in Chicago, police shoot and kill 2 people. Local anarchists call for a rally on May 4, at Haymarket Square. Thousands show up and listen to speeches until police move in to disperse the crowd, and somebody throws a bomb. One officer is killed and many wounded. Guns fire in all directions, and when it stops, 7 policemen and at least 4 demonstrators are dead; scores are injured. The police crack down and eight anarchists are arrested. Though none had thrown the bomb, four are hanged. 40 hour work weeks become federal law in 1938.