System. The organization of the Knights of Labor in 1869 had increased its membership to 400,000 in 1884. One of the principle objects of this organization was the establishment of the eight-hour system of labor. At this date, 1884, a million organized wage-workers in the Unites States considered the establishment of the eight-hour system one of the main objects of their organization. The agitation for a reduction of the hours of labor culminated in the strike of 360,000 men on May 1, 1886. In Chicago, the center of the eight-hour movement, over 40,000 workmen went on a strike for the eight-hour work day. On May 3 some of the strikers were fired on by the police, killing one and wounding several. On May 4 workingmen held an indignation meeting which was broken up by the police, when a dynamite bomb was thrown, which killed seven policemen and wounded many persons.