Canto 1 - Boyhood
Bāla-kāṇḍa
Chapter 67: Lord Rāma Breaks Lord Śiva’s bow
Text 1.67.18
तस्य शब्दो महानासीन्निर्घातसमनिःस्वनः।
भूमिकम्पश्च सुमहान्पर्वतस्येव दीर्यतः॥
tasya śabdo mahān āsīn nirghāta-sama-niḥsvanaḥ
bhūmi-kampaś ca sumahān parvatasyeva dīryataḥ
tasya śabdaḥ mahān āsīt = that breaking caused a great sound vibration; nirghāta-sama-niḥsvanaḥ = equal to the sound of a nirghāta; bhūmi-kampaḥ = earthquake; ca = and; sumahān = a very great; parvatasya= of a mountain; iva = that resembled; dīryataḥ = the destruction.
That breaking caused a great sound vibration equal to the sound of a nirghāta and a very great earthquake that resembled the destruction of a mountain.
Nirghāta has been defined in the Jyotiṣa-śāstras:
vāyunābhihato vāyur gaganāt patati kṣitau
yadā dīptaḥ khaga-rutaḥ sa nirghāto ’tidoṣakṛt
“Nirghāta is the phenomenon when wind clashes with wind and falls on the earth from the sky, and when the sound of the birds [in the sky under that circumstance] is excited. It creates extreme disturbance.”