Throughout history, most people have lived by the celestial clock of night and day, and by the biological clock of hunger and thirst. Alongside civilization developed the astonishing idea that the day might be divided and subdivided into regular units of time, each with their appropriate behaviors and endeavors. Since the monastic era in the West, this organization by hours has become so entrenched that time as we perceive it has come almost to seem uncaused, a fact of nature. Now Kevin Jackson restores its strangeness and richness. From the structure of the working day to the imposition of curfews, from the scheduling of public events to the content of etiquette, in a manner no less remarkable for being rarely remarked, the hours give a meaning to our days. Here then are the hours, from dawn to Eliot's "uncertain hour before dawn" by way of elevens and the lunch hour, the hours for siesta, vespers and the witching hour.