Matsya Purana — Eclipse-Time Planetary Bath
प्राङ्मुखः पूजयित्वा तु नमस्यन्निष्टदेवताम् चन्द्रग्रहे विनिर्वृत्ते कृतगोदानमङ्गलः कृतस्नानाय तं पट्टं ब्राह्मणाय निवेदयेत् //
prāṅmukhaḥ pūjayitvā tu namasyanniṣṭadevatām candragrahe vinirvṛtte kṛtagodānamaṅgalaḥ kṛtasnānāya taṃ paṭṭaṃ brāhmaṇāya nivedayet //
面向东方,礼拜并顶礼自选所奉之本尊。待月食既毕,依仪成就施牛之吉祥功德,并沐浴净身后,当将彼布帛(paṭṭa)奉献于一位婆罗门。
This verse does not address pralaya; it focuses on post-eclipse (grahaṇa) ritual purification, worship, and meritorious donation as part of dharma.
It frames a householder’s (and by extension a king’s) duty to observe purity and charity: worship facing east, bathe after the eclipse, and complete prescribed gifts—especially go-dāna and gifting cloth to a brāhmaṇa—reflecting social-religious responsibility and merit-making.
The significance is ritual (not architectural): correct orientation (facing east), eclipse-closure timing, bathing (snāna) for purification, and the prescribed donations (cow and cloth) culminating in a brāhmaṇa offering.