कोष्ठागारे वर्षमानमरत्निमुखं कुण्डं स्थापयेत् ॥ कZ_०२.५.०७ ॥
koṣṭhāgāre varṣamānam aratnimukhaṃ kuṇḍaṃ sthāpayet.
In the storehouse, he should install a measuring vessel (kuṇḍa) for rainfall measurement, with an opening one aratni (cubit) wide.
Rainfall data directly informs expected yield, procurement, storage targets, and famine-prevention logistics—core functions tied to the granary.