YV 3.5j

In that he puts down the 'sitters on the vault', the sacrificer thus goes by the 'sitters on the vault' to the world of heaven; the vault is the world of heaven; for him for whom these are put down there is no misfortune (náákam); the 'sitters on the vault' are the home of the sacrificer; in that he puts down the 'sitters on the vault', the sacrificer thus makes himself a home. The 'sitters on the vault' are the collected brilliance of the Prstha (Stotras); in that he puts down the 'sitters on the vault' [1], verily he wins the brilliance of the Prsthas. He puts down the five crested; verily becoming Apsarases they wait on him in yonder world; verily also they are the bodyguards of the sacrificer. He should think of whomever he hates as he puts (them) down; verily he cuts him off for these deities; swiftly he goes to ruin. He puts (them) above the 'sitters on the vault'; that is as when having taken a wife one seats her in the house [2]; he puts the highest on the west, pointing east; therefore the wife attends on the west, facing east. He puts as the highest the naturally perforated and the earless (bricks); the naturally perforated is breath, the earless is life; verily he places breath and life as the highest of the breaths; therefore are breath and life the highest of the breaths. No brick higher (than these) should he put down; if he were to put another brick higher, he would obstruct the breath and life of cattle [3] and of the sacrificer; there fore no other brick should be put down higher. He puts down the naturally perforated brick; the naturally perforated brick is yonder (sky); verily he puts down yonder (sky). He makes the horse sniff it; verily be places breath in it; again the horse is connected with Prajapati; verily by Prajapati he piles the fire. It is naturally perforated, to let out the breaths, and also to light up the world of heaven.