Matsya Purana — Account of the Manvantaras: Manus
ततस्तु मेरुसावर्णिर् ब्रह्मसूनुर् मनुः स्मृतः ऋतश्च ऋतधामा च विष्वक्सेनो मनुस् तथा //
tatastu merusāvarṇir brahmasūnur manuḥ smṛtaḥ ṛtaśca ṛtadhāmā ca viṣvakseno manus tathā //
Thereafter, Merusāvarṇi—Brahmā’s son—is remembered as a Manu; likewise Ṛta and Ṛtadhāmā, and also Viṣvaksena, are counted among the Manus.
It situates cosmic time into recurring Manvantaras by naming Manus; this is part of the Purāṇic chronology that frames creation, maintenance, and periodic dissolutions, though Pralaya itself is not described in this specific verse.
By identifying Manus—archetypal lawgivers and rulers of epochs—the verse indirectly grounds dharma in Manu-led cosmic administration; kings and householders are understood to follow the dharmic order maintained in each Manvantara.
No direct Vāstu, temple-building, or ritual procedure is stated; the verse is primarily a genealogical/chronological listing of Manvantara figures.