Page:Aryabhatiya of Aryabhata, English translation.djvu/103

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GOLA OR THE SPHERE 73

and Bhaskara, Golddhydya, Tri'prasnavdsand, 36, sankuv unnatalavajyakd hhavet}

Paramesvara remarks: uttaragole gatagantavyd- suhhyas caradaldsun visodhya jivdm dddya svdhord- trdrdhena nihatya trijyayd vibhajya lahdhe hhujydm praksipet. sd ksitijdd utpannd svdhoratrestajyd bhavati. This corresponds to the so-called cheda of Brahma- gupta.

29. Multiply the given sine of altitude of the Sun by the sine of latitude (the equinoctial sine) and di%"ide by the sine of co- latitude. The result mil be the base of the sahku of the Sun south of the rising and setting line.

Sankvagra is the same as sankutala {"the base of the sanku") and denotes the distance of the base of the sanku from the rising and setting line.^

30. The sine of the greatest decUnation multiplied by the given basersine„pf„the»Sun and divided by the sine of co-latitude is the Sun's agra on the east and west horizons.

The agrd is the Sun's amplitude or the sine of the degrees of difference between the day-circle and the east and west points on the horizon.^

The proportions employed are those given in Suryasiddhdnta, V, 3 n.

1 Cf. SHryasiddhanta, III, 35-39 and note; Brahmagupta, III, 25-26; BCMS, XVIII (1927), 25.

2 Cf. Brahmagupta, III, 65 and XXI, 63; Bhaskara, Goladhyaya, Triprainavasana, 40-42 (and Vdsandbhdsya) and Ganitadhyaya, Tri- pra§nMhikara, 73 (and Vasanabha§ya) ; Lalla, Triprainadhikara, 49.

  • See S-uryasiddhanta, III, 7 n.; Brahmagupta, XXI, 61; Bhas-

kara, Goladhy&ya, Tri-praknavdsana, 39 and GavitadhySya, Tripraina- dhikara, 17 (yssanabhd§ya).