सिद्धान्तशिरोमणि: गणिताध्याय (भास्कराचार्य - ग्रहगणित, मध्यमाधिकार व स्पष्टाधिकार सटीक)

25 .

solar and luni-solar years begin simultaneously this year,
by the end of the luni-solar year, it will have gained over
the solar year the above-mentioned days. This difference
which goes by the name Adhimasa-Sesha or Suddhi
accrues to the length of a lunation in about 32½ solar
months. Unless this accruing difference is set apart by some
device, and the beginnings of the two years again brought
together, the luni-Solar year looses its significance of an
year, for, it does not accord with seasons. It being a con-
vention that an year should begin with the spring, if the
luni-Solar year also is to begin with the spring, it is to be
wedded to the solar year by some device. The device
adopted in this behalf was to leave out a month in the luni-
Solar reckoning as soon as it could be seen that a month
has been gained by this reckoning over the solar. This
knowledge is had from the following fact. The zodiac is
divided into twelve equal portions called Rasi's beginning
from the first point of the Hindu Zodiac, ie. from the first
point of the asterism division called Aswini. The Sun
traverses each of these Rasis in one Solar month, and on
account of the unequal motion of the Sun, these solar
months are of unequal length. The entrance of the Sun
from one Rasi into another is called a Samkrānti, and the
moments of Samkrāntis are held to be holy for religious pur-
poses. The solar month being a little longer than a luna-
tion, normally a Samkrānti occurs in a lunation. But it
so happens that in a particular lunar month this Samkrānti
might not occur. The Suddhi which is the time between
the moment of New Moon and the subsequent Samkrānti
and which is therefore the time gained by the luni-Solar
reckoning over the Solar, having accrued to a lunation, it
is an indication that the luni-Solar reckoning has gained a
lunation over the Solar. That lunation not carrying a
Samkrānti is termed an Adhikamasa and is left out. That
it is left out is connoted by the word Adhika which means
extra, as well as by the convention that no auspicious
celebrations like a marriage etc. should not take place
4