Because much of the infantry went underground, it was no longer possible simply to holler or sound a hunting horn as a signal to attack, nor for regiments to advance proudly, and visibly, together on horseback. Instead, it became necessary to coordinate time and to tell it accurately; the practice and the phrase synchronize watcheswas born from this need during the war. Officers in crowded trenches watched for second hands to tick down before blowing the whistle and rallying their men, who scrambled up ladders into the awaiting gunfire.
.. Since the eighteenth century, gentlemen who needed to tell time—and wanted to display their wealth—carried pocket watches, either an open-faced design or a model with a spring-loaded cover to protect its delicate hands and face from damage. Most ordinary people didn’t need to know that it was seven thirty in the evening rather than dusk; they told time by church bells, sunrises, and habit. It wasn’t until the expansion of railroads in the middle of the nineteenth century that minutes truly became measured, timetabled, and synchronized.