ENCE

It has been necessary to bear in mind these phases of practical
civilization because much that we know of the purely scientific
attainments of the Egyptians is based upon modern observation of their
pyramids and temples. It was early observed, for example, that the
pyramids are obviously oriented as regards the direction in which they
face, in strict accordance with some astronomical principle. Early in
the nineteenth century the Frenchman Biot made interesting studies in
regard to this subject, and a hundred years later, in our own time, Sir
Joseph Norman Lockyer, following up the work of various intermediary
observers, has given the subject much attention, making it the central
theme of his work on The Dawn of Astronomy.(1) Lockyer's researches
make it clear that in the main the temples of Egypt were oriented with
reference to the point at which the sun rises on the day of the summer
solstice. The time of the solstice had peculiar interest for the
Egyptians, because it corresponded rather closely with the time of the
rising of the Nile. The floods of that river appear with very great
regularity; the on-rushing tide reaches the region of Heliopolis and
Memphis almost precisely on the day of the summer solstice. The
time varies at different stages of the river's course, but as the
civilization of the early dynasties centred at Memphis, observations
made at this place had widest vogue.

Considering the all-essential character of the Nile floods-without which
civilization would be impossible in Egypt--it is not strange that the
time of their appearance should be taken as marking the beginning of a
new year. The fact that their coming coincides with the solstice makes
such a division of the calendar perfectly natural. In point of fact,
from the earliest periods of which records have come down to us, the new
year of the Egyptians dates from the summer solstice. It is certain that
from the earliest historical periods the Egyptians were aware of the
approximate length of the year. It would be strange were it otherwise,
considering the ease with which a record of days could be kept from Nile
flood to Nile flood, or from solstice to solstice. But this, of course,
applies only to an approximate count. There is some reason to believe
that in the earliest period the Egyptians made this count only 360 days.
The fact that their year was divided into twelve months of thirty days
each lends color to this belief; but, in any eve