कृषि-पाराशर (महर्षि पराशर - प्राचीन भारतीय कृषि, मृदा-परीक्षण, वर्षा-पूर्वानुमान व बीज-संस्कार)

66 KṚṢI-PARĀŚARA
Now knowledge of rainfall in Pauṣa
30. A wise man should ascertain the monthly rainfall or drought
beginning with Pauṣa according to the course of the wind after
taking a unit of two days and a half (of Pauṣa)
31. (Wind) from the north or west (indicates) rainfall and
(that) from the east or south (indicates) drought; there being absence
of wind there will be absence of rainfall and wind being fitful irregular
rainfall (takes place).
32. A unit of five daṇḍas is considered to (represent) a day of
the (corresponding) month. (Rainfall) in the earlier and latter parts
(indicates) diurnal or nocturnal rainfall¹ (respectively in corresponding
months).
33. By attaching a flag to a post,² and making efforts day and
night, the monthly rainfall is to be ascertained according to the course
of the wind.
34. When, in the bright fortnight of the month of Pauṣa, the
sky is whitened with dust, and the western horizon is dazzled by
flashes of lightning, then (i.e. such circumstances will indicate that)
the entire earth will be flooded with water.
35. If there be a shower or fog in the month of Pauṣa, then the
earth will become full of water in the seventh month therefrom.
36. If, in the bright fortnight of the month of Pauṣa, the sky
becomes overcast with clouds, then, in that year, the earth becomes
covered with water.
37. If it rains in the period between Pisces and Scorpio, then,
in that very lunar mansion of the seventh month therefrom, the earth
becomes inundated.
Now the knowledge of rainfall in Māgha
38. If, on the seventh day of the bright half of Māgha, there
be a shower or the sight (i.e. accumulation) of clouds, then the year
(becomes) blessed yielding all crops.
1 S. P. Roy Chaudhuri, in the Agricultural Practices, etc., points out that
this seems to testify to the ancient Indians' knowledge of the distinction between
the effects of rainfall by day and at night.
2 This appears to indicate the use of weather-vanes in those days.