Manipulate the big 2nd hand and cooperate Together with the nine o'clock dial to properly depend the seconds Perhaps most vital with respect to horological history writ large was the debut with the “Omega” caliber in 1894, a 19-ligne, crown-set motion whose interchangeable elements had been meant for uncomplicated company. https://www.watchesworld.com/a-history-of-watch-reference-numbers/