...doing Kriya -- cold air (vayu) moves within and outside the spine.
- Lahiri Mahasaya from Gita Commentary 10:25, Yoga Niketan
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Or here is another translation of the same verse:
Eternal kootasth (vibration) - doing kriya the cool air goes in and out of the meru.
[Comment: Meru is defined at the end of the commentary on this verse as “spinal cord”]
- Spiritual Gita (of Shyama Charan Lahiri Mahasaya and Sri Sanyal Mahasaya) translated by Smt. Chandrakanta Agarwala