A semitone, also called a half step or a half tone, is the smallest musical interval commonly used in Western tonal music, and it is considered the most dissonant when sounded harmonically. It is defined as the interval between two adjacent notes in a 12-tone scale (e.g. from C to C â¯).
The National Labor Union. The first large-scale U.S. union was the National Labor Union, founded in 1866 to organize skilled and unskilled laborers, farmers, and factory workers.
The Most Famous Labor Union in History. In the history of America's trade and labor unions, the most famous union remains the American Federation of Labor (AFL), founded in 1886 by Samuel Gompers. At its pinnacle, the AFL had approximately 1.4 million members.