Matsya Purana — Navagraha Sacrifice for Planetary Pacification and Prosperity
वृत्तं वोच्चाटने कुण्डं तथा च वश्यकर्मणि त्रिमेखलं चैकवक्त्रम् अरत्निर्विस्तरेण तु //
vṛttaṃ voccāṭane kuṇḍaṃ tathā ca vaśyakarmaṇi trimekhalaṃ caikavaktram aratnirvistareṇa tu //
For rites of driving away (uccāṭana), the fire-pit (kuṇḍa) should be circular; likewise for rites of subjugation (vaśyakarma). It should be made with three girdling lines (tri-mekhala), with a single opening/face (eka-vaktra), and with a breadth of one aratni (cubit/forearm).
This verse does not discuss pralaya; it focuses on ritual architecture—specifically the prescribed shape and measurements of a kuṇḍa used in specialized rites.
It frames ritual practice as rule-governed: a king or householder who sponsors rites should follow precise śāstric specifications (shape, bands, and measurements) to ensure the rite is performed correctly and responsibly.
It prescribes a circular kuṇḍa with three encircling boundary lines (tri-mekhala), a single principal opening/face (eka-vaktra), and a standard breadth of one aratni—key technical parameters in Matsya Purana ritual design.