Adams, Walter M.: The house of the hidden places: a clue to the creed of early Egypt from Egyptian sources (London, 1895)

136 The Mystery of the Heavens. [Ch.

hours every year. Consequently there will be
in each year one day when that star will rise
at that place " heliacally," that is to say, just
so long before the dawn as to be visible for a
few moments on the horizon before vanishing
in the increasing splendour. The position of
the star relatively to the earth and sun at
the moment of heliacal rising we may call its
orient; and when the position is such as to
coincide with the summer solstice, we may
express that position as the Grand Orient of
the star. Now the number of degrees by
which the sun is below the horizon when the
heliacal rising of a star takes place, is not
fully determined, and varies to some extent
with the locality; but ten degrees below is
usually taken as the sun's position when the
star is lost in dawn, so that the time would
be about forty minutes before full sunrise.
Let us consider now the interval between
two such risings of some particular star ; and
for that purpose let us choose, like the