months to this day. _Suidas_ [62] tells us, that the _Sarus_ of the
_Chaldeans_ contains 222 Lunar months, which are eighteen years, consisting
each of twelve Lunar months, besides six intercalary months: and when [63]
_Cyrus_ cut the River _Gindus_ into 360 Channels, he seems to have alluded
unto the number of days in the Calendar year of the _Medes_ and _Persians_:
and the Emperor _Julian_ [64] writes, _For when all other People, that I
may say it in one word, accommodate their months to the course of the Moon,
we alone with the _Egyptians_ measure the days of the year by the course of
the Sun._

At length the _Egyptians_, for the sake of Navigation, applied themselves
to observe the Stars; and by their Heliacal Risings and Settings found the
true Solar year to be five days longer than the Calendar year, and
therefore added five days to the twelve Calendar months; making the Solar
year to consist of twelve months and five days. _Strabo_ [65] and [66]
_Diodorus_ ascribe this invention to the _Egyptians_ of _Thebes_. _The
_Theban_ Priests_, saith _Strabo_, _are above others said to be Astronomers
and Philosophers. They invented the reckoning of days not by the course of
the Moon, but by the course of the Sun. To twelve months each of thirty
days they add yearly five days._ In memory of this Emendation of the year
they dedicated the [67] five additional days to _Osiris_, _Isis_, _Orus_
senior, _Typhon_, and _Nephthe_ the wife of _Typhon_, feigning that those
days were added to the year when these five Princes were born, that is, in
the Reign of _Ouranus_, or _Ammon_, the father of _Sesac_: and in [68] the
Sepulchre of _Amenophis_, who Reigned soon after, they placed a Golden
Circle of 365 cubits in compass, and divided it into 365 equal parts, to
represent all the days in the year, and noted upon each part the Heliacal
Risings and Settings of the Stars on that day; which Circle remained there
'till the invasion of _Egypt_ by _Cambyses_ King of _Persia_. 'Till the
Reign of _Ouranus_, the father of _Hyperion_, and grandfather of _Helius_