There are indications that yoga (meditation) was practised (or at least prescribed) between the two phases of sleep, at midnight, in Pāñcarātra texts – Marion Rastelli has written a bit on this in her paper "Yoga in the Daily Routine of the Pāñcarātrins" - I can send you a pdf of this paper if you like,

Best wishes,
Robert

On Mon, Jan 10, 2022 at 1:52 PM Jonathan Silk via INDOLOGY <indology@list.indology.info> wrote:
Dear Colleagues

I just read an interesting article: https://www.bbc.com/future/article/20220107-the-lost-medieval-habit-of-biphasic-sleep

this led me to wonder whether anyone has run across any indications in Skt (or Tamil) literature of this so-called biphasic sleep.

Best thanks in advance,
Jonathan

--
J. Silk
Leiden University
Leiden University Institute for Area Studies, LIAS
Matthias de Vrieshof 3, Room 0.05b
2311 BZ Leiden
The Netherlands

copies of my publications may be found at

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