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READING PASSAGE 6
A Chronicle of Timekeeping
Our conception of time depends on the way we measure it
A
According to archaeological evidence, at least 5,000 years ago, and long before the advent of the Roman
Empire, the Babylonians began to measure time, introducing calendars to co-ordinate communal activities, to
plan the shipment of goods and, in particular, to regulate planting and harvesting. They based their calendars
on three natural cycles: the solar day, marked by the successive periods of light and darkness as the earth
rotates on its axis; the lunar month, following the phases of the moon as it orbits the earth; and the solar year,
defined by the changing seasons that accompany our planet's revolution around the sun.
B
Before the invention of artificial light, the moon had greater social impact. And, for those living near the
equator in particular, its waxing and waning was more conspicuous than the passing of the seasons. Hence, the
calendars that were developed at the lower latitudes were influenced more by the lunar cycle than by the solar
year. In more northern climes, however, where seasonal agriculture was practised, the solar year became
more crucial. As the Roman Empire expanded northward, it organised its activity chart for the most
