Kautilya's Arthashastra 2.31.6

2.31.6

pūrvāhne vyāyāmakālaḥ, paścāhnaḥ pratipānakālaḥ //

The first and the seventh of the eight divisions of the day are the two bathing times of elephants; the time subsequent to those two periods is for their food; forenoon is the time for their exercise; afternoon is the time for drink; two (out of eight) parts of the night are the time for sleep; one-third of the night is spent in taking wakeful rest.