Canto 1 - Boyhood
Bāla-kāṇḍa
Chapter 40: Lord Kapila Punishes Sagara’s Sons
Text 1.40.15

यदा पर्वणि काकुत्स्थ विश्रमार्थं महागजः।
खेदाच्चालयते शीर्षं भूमिकम्पस्तदा भवेत्॥

yadā parvaṇi kākutstha viśramārthaṁ mahā-gajaḥ
khedāc
cālayate śīrṣaṁ bhūmi-kampas tadā bhavet

yadā parvaṇi = on the day when; kākutstha = O Kakutstha; viśrama-artham = to mitigate; mahā-gajaḥ = the great elephant; khedāt = its discomfort; cālayate = moves; śīrṣam = its head; bhūmi-kampaḥ = an earthquake; tadā bhavet = occurs.

O Kākutstha, an earthquake occurs on the day when the great elephant moves its head to mitigate its discomfort.