Śatapatha Brāhmaṇa ("of a hundred paths") 4.2.4.13

4.2.4.13

taṃ gṛhītvottare havirdhāne sādayati prāṇā vai grahā netprāṇānmohayānītyupakīrṇe vā itarāngrahānsādayatyathaitaṃ vyuhya na tṛṇaṃ canāntardhāya

Having drawn it (the Dhruva graha), he deposits it with the northern cart, lest he should confound the vital airs, for the grahas are vital airs: now the other grahas he deposits on the raised (mound), but this one (he deposits) after pushing (the dust) aside without leaving as much as a blade of grass between.