Kautilya's Arthashastra 1.20.4

1.20.4

mānuṣeṇāgninā trir apasavyaṃ parigatam antaḥpuram agnir anyo na dahati, na cātrānyo 'gnir jvalati, vaidyutena bhasmanā mṛtsamyuktena karakavāriṇāvaliptaṃ ca //

No other kind of fire can burn that harem which is thrice circumambulated from right to left by a fire of human make (manushénágnina); nor can there be kindled any other fire. Nor can fire destroy that harem the walls of which are made of mud mixed with ashes produced by lightning, and wetted in hail-water (karaka-vári).