Śatapatha Brāhmaṇa ("of a hundred paths") 1.3.4.15

1.3.4.15

sa vā upari juhūṃ sādayati | adha itarāḥ srucaḥ kṣatraṃvai juhūrviśa itarāḥ srucaḥ kṣatramevaitadviśa uttaraṃ karoti tasmāduparyāsīnaṃ kṣatriyamadhastādimāḥ prajā upāsate tasmāduparijuhūṃ sādayatyadha itarāḥ srucaḥ

He lays the guhû down on (the prastara), and the other spoons down below, (viz. on the barhis, north of the guhû, and so as not to touch it or one another); for the guhû assuredly is the kshatra, and the other spoons (sruk) are the vis: he thereby makes the kshatra superior to the vis. Hence the people here serve, from a lower position, the Kshatriya seated above them: for this reason he places the guhû upon (the prastara) and the other spoons down below it.