JULIAN Period, in chronology, a period so called, as
being adapted to the Julian year.
It is made to commence before the creation of the
world. Its principal advantage lies here, that the
same years of the cycles of the sun, moon, and indic-
tion, of which three cycles it was made to consist by
Joseph Scaliger in 1580, belonging to any year of this
period, will never fall together again till after the ex-
piration of 7980 years. There is taken for the first
year of this period that which hath the first of the
cycle of the sun, the first of the cycle of the moon,
and the first of the indiction cycle, and so reckon-
ing on.
The first year of the Christian era is always, in our
systems of chronology, the 4714th of the Julian
period.
To find what year of the Julian period any given
year of Christ answers to: To the given year of Christ
add 4713, because so many years of the Julian period
were expired A. D. 1; and the sum gives the year of
the Julian period sought.
On the contrary, having the year of the Julian pe-
riod given, to find what year of Christ answers thereto:
From the year of the Julian period given subtract
4713, and the remainder will be the year sought.