Satapatha Brahmana Part II (SBE26), Julius Eggeling tr. [1885], at sacred-texts.com
4:6:2:11. Verily, they who sit (sacrificing) for a year, by means of six months go to him that burns yonder:
so it is told on the part of the Sâman, in as much as it is made of the form of that (sun) it is told on the part of the Rik 1; and now in like manner on the part of the Yagus, by means of preparatory rite, when they draw that (graha) 2, they thereby also go to him (the sun).
4:6:2:22. He thus takes it therefrom with (Vâg. S. VIII, 41; Rig-veda I, 50, 1) 1, 'The lights bear on high that divine knower of beings, Sûrya, that all may see him!--Thou art drawn with a support: thee to Sûrya nor splendour!--This is thy womb: thee to Sûrya for splendour!'
426:3 The great sacrificial session (sattra), called Gavâm ayana, or p. 427 cows' walk (or course), usually extends over twelve months (of 30 days), and consists of the following parts:
Katurvimsa day, an Ukthya, all the stotras of which are in the Katurvimsa stoma.
Five months, each consisting of four Abhiplava shadahas and one Prishthya shadaha (= 30 days). Cf. p. 402, n. 2.
28 days, which, with the two opening days, complete the sixth month:
VISHUVANT or central day.
28 days, which, with the two concluding days, complete the seventh month:
Four months, each consisting of four Abhiplavas and one Prishthya.
30 days:
Mahâvrata day.
Udayanîya Atirâtra.
In imitation of the retrograde course of the sun, the order of the performance during the second part of the year is, generally speaking, the reverse of that of the former half.
427:1 Ta etam shadbhir mâsair yanti, tasmât parâñko grahâ grihyante parâñki stotrâni parâñki sastrâni. Ta etam shashthe mâse gakhanti tad etasya rûpam kriyate. Kânva text.
427:2 Viz. the Atigrâhya cup to Sûrya (IV, 5, 4, 2 seq.), which has p. 428 to be drawn on the Vishuvant or middle day of the Gavâm ayana; an animal sacrifice to the same deity being also prescribed.
428:1 The Kânva text allows the alternative mantra, Rig-veda I, 50, 3; Vâg. S. VIII, 40, Adrisram asya ketavah, &c. See IV, 5, 4, 11.