Electrical Aptitude Practice Test 1

The Wandering Year: Ancient Egypt's Civil Calendar

¹Life in ancient Egypt depended on the Nile River, which flooded its valley every year and left behind rich soil for farming. To plan their work, Egyptians kept track of time in more than one way. For religious festivals they used a lunar calendar, in which each month began on the morning when the thin crescent of the old moon could no longer be seen. Lunar months, however, do not fit evenly into a year of seasons, so for government records and daily business the Egyptians also used a civil calendar of fixed length.

²The civil year had 365 days. It was made up of twelve months of 30 days each, for a total of 360 days, followed by five extra days that belonged to no month at all. Historians call these the epagomenal days. Egyptians linked them with the births of gods and also thought of them as a dangerous time. Each 30-day month was further divided into three periods of ten days.

³The twelve months were grouped into three seasons of four months each, named for stages of the farming year. Akhet, the inundation, was the season of the flood. Peret, the emergence, came as the water drained away and the fields appeared and were planted. Shemu, the season of low water, was the time of harvest. The civil year was apparently set up so that New Year's Day fell on the heliacal rising of Sirius, the morning when that bright star, called Sopdet by the Egyptians, first reappeared at dawn after weeks hidden in the glare of the sun.

⁴The calendar had one flaw. The true solar year is about a quarter of a day longer than 365 days, and the civil year had no leap day to make up the difference. As a result, the calendar slipped against the seasons by about one day every four years. After a century, New Year's Day came roughly 25 days away from the rising of Sirius, and only after about 1,460 years did the two meet again. Because of this slow drift, the civil calendar is often called the "wandering year."

⁵Efforts to fix the problem met resistance. In 238 BC, King Ptolemy III issued the Canopus Decree, which ordered a sixth extra day to be added every fourth year. Priests and ordinary Egyptians largely ignored the order, and it was abandoned. A lasting reform came only under Roman rule, when Augustus introduced a regular leap day in about 25 BC. The reformed calendar, known as the Alexandrian calendar, later became the basis of the Coptic calendar.