Arthashastra
विद्युत् प्रदग्धो अङ्गारो ज्वालो वा विद्युत् प्रदग्धैः काष्ठैर् गृहीतश् च अनुवासितः कृत्तिकासु भरणीषु वा रौद्रेण कर्मणा अभिहुतो अग्निः प्रणीतश् च निस्प्रतीकारो दहति ॥
When, on the days of the stars of krittiká or bharaní and following the method of performing fearful rites, an oblation with a black cobra emitting froth at the shock of lightning or caught hold of by means of the sticks of a tree struck by lightning and perfumed is made into the fire, that fire continues to burn unquenchably.
english translation
vidyut pradagdho aGgAro jvAlo vA vidyut pradagdhaiH kASThair gRhItaz ca anuvAsitaH kRttikAsu bharaNISu vA raudreNa karmaNA abhihuto agniH praNItaz ca nispratIkAro dahati ॥
hk transliteration by Sanscript