The late 19th century was politically turbulent. This poster comes from a pamphlet ad for watches, from 1887. The year before, a bomb had exploded at a labor union meeting in Chicago's Haymarket Square. Workers were demanding an eight hour day, and a large crowd had gathered. The bomb thrower killed seven policemen. Surviving police fired into the crowd, killing four. The bomb thrower was never found, but "anarchists" were suspected.
The men named on the poster--Johann Most, O'Donovan Rossa--were famous anarchists and political dissenters. The ad asks the viewer to be on guard, to look out for deception, for false appearances, for trouble. The last page appears below.
It tells workers that they are safe if they internalize the time discipline of the watch. There's no need to watch the watch owner--he already watches himself.
As the next page shows, this sort of time discipline was essential to business.