Agniveshyagrihyasutra 2.6.8.1

2.6.8.1

athāparāhṇe tāmramayaṃ vā mṛṇmayaṃ vā kamaṇḍalumādāya grāmāt prācīmudicīṃ vā diśamupaniṣkramya tīrthe gatvodakaṃ gṛhītvā śucau deśe śaucārthe mṛdaṃ parigṛhya nasiktaṃ napurīṣaṃ noṣaraṃ navalmīkaṃ naśarkarāmiśraṃ naśāḍvalamiśraṃ karṇasthabrahmamūtraḥ pavitramasi iti tṛṇairavakīrya teṣu mūtrapurīṣaṃ visṛjati \

Then, in the afternoon, having taken a copper or earthen water-pot, having gone out from the village toward the east or north, having gone to a sacred spot and taken water, having taken earth for purification in a clean place—neither moist, nor with feces, nor saline, nor an anthill, nor mixed with gravel, nor mixed with grassy turf—having placed the sacred thread over his ear, having scattered grass with: "You are a strainer," he discharges urine and feces on it.