UNESCO Ancient Civilizations of Africa (Editor G. Mokhtar)

Introduction
used a natural calendar based on the periodic repetition of an event that
was all-important for their existence - the flood of the Nile.
In that calendar the first season of the year, called 'Akhet' in
Egyptian, saw the beginning of the flood. The river's waters rose little by
little and covered the land dried up by the torrid summer. For about four
months the fields would become saturated with water. In the next season
the land gradually emerging from the flood waters became ready for
sowing. This was the season of Peret, literally 'coming out', a term that
no doubt alludes both to the 'coming out' of the land from the water
and the 'coming out' of the vegetation. Once sowing was over the peasant
awaited germination, then the ripening of the grain. In the third and
final season the Egyptians harvested and then stored the harvest. After
that they had only to await the new flood and to prepare the fieldsfor its
arrival. This was the season of Shemou.
It is possible, and even highly probable, that for a very long time the
Egyptians were satisfied with this calendar. The year then began with
the actual rise of the waters. The season of Akhet so initiated lasted to the
actual retirement of the waters, which marked the commencement of the
season of Peret. This in turn ended when the ripened grain was ready for
the sickle, marking the beginning of the season of Shemou, which
ended only with the new rise. It mattered little to the peasant that one
season might be longer than another; what mattered to him was the
organization of his work, which varied according to the three seasons.
At what moment and for what reasons did the Egyptians link the flood of
the Nile with the simultaneous appearance on the horizon of the sun and
the star Sothis? This will surely be difficult to determine. No doubt that
linking was the result both of repeated observations and of profound
religious beliefs. The star Sothis (Sirius), in Egyptian Sepedet, the Pointed
One, was later to be identified with Isis, whose tears were thought to
determine the flood of the Nile. Perhaps we have here the reflection of a
very ancient belief associating the appearance of the deified star with the
rise of the waters. Whatever their reasons, by linking the beginning of
the flood, and consequently the first day of the new year, with an
astronomical phenomenon, the Egyptians have provided us with a means
of setting positive reference points for their long history.
At the latitude of Memphis the very gentle beginning of the flood took
place about the middle of July. Observation over a few years appears to have
sufficed to show the Egyptians that the beginning of the flood recurred
on average every 365 days. They thereupon divided their year of three
empirical seasons into a year of twelve months of thirty days each. They
then assigned four months to each of the seasons. By adding five
additional days (in Egyptian the '5 heryou renepet', the five over - in
addition to — the year), which the Greeks called the 'epagomenes', the
scribes obtained a year of 365 days, which was by far the best of all those
adopted in antiquity. However, although very good, that year was not
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