Garudapurana 1.197.10

1.197.10

trikoṇaṃ svasthikairyuktaṃ jvālāmā lānalaṃ smaret /
bhinnāñjananibhākāraṃ svavṛttaṃ bindubhūṣitam //

triangular, marked with svastikas, blazing with wreaths of flames, one should contemplate fire; / [and air] resembling broken collyrium, a circle of its own, adorned with a dot;