Solar Plexus

Manipura, the city of jewels, is described in the Sat-Cakra-Nirupana as a lotus of ten petals at the navel, bearing the letters dam through pham. Within it is a red triangle with swastika marks at its sides, the region of fire, with the seed syllable RAM seated on a ram; the presiding deity is Rudra with the shakti Lakini. The association of the navel region with fire connects to a much wider Indian medical and yogic idea of the digestive fire, agni or jatharagni, which is central to Ayurveda, so this is one of the centres where the tantric scheme meets an older and independent physiological doctrine. The correspondence with the solar plexus is a modern anatomical gloss, not a term the Sanskrit sources use.

The idea that the navel region houses a fire with wider significance than digestion recurs outside the Hindu tantric tradition as well: in Tibetan Vajrayana Buddhism, the practice known as tummo, inner heat, one of the Six Yogas of Naropa, is centred on the navel and is used to generate physical warmth and, in the tradition's own account, to support more advanced stages of meditation, an independent development rather than a borrowing from the Sanskrit Sat-Cakra-Nirupana but a recognisable case of the same body region being read, in two separate tantric traditions, as a seat of heat and transformative power.

Sources The Serpent PowerSir John Woodroffe (Arthur Avalon) with The Origins of Yoga and Tantra: Indic Religions to the Thirteenth CenturyGeoffrey Samuel

The second decisive figure after Woodroffe is Charles Webster Leadbeater, a Theosophical writer whose book The Chakras appeared in 1927 and whose colour plates of glowing vortices are the direct ancestor of nearly every modern chakra illustration. Leadbeater described the centres as funnel-shaped whirlpools of force on the surface of the etheric body, said he perceived them clairvoyantly, and assigned them colours; he also linked them to the endocrine glands, an association that has no basis in the Sanskrit texts and that has since been repeated everywhere. His colour assignments were his own and do not match either the tantric texts or the rainbow scheme now in use. The atlas records the tantric material and the theosophical material separately because they are separate; conflating them, which most popular writing does, makes a modern synthesis look ancient.

The specific endocrine pairings that later popular writing attached to Leadbeater's scheme, and that remain the standard list in wellness literature today, run from bottom to top: Muladhara to the adrenal glands, Svadhisthana to the gonads, Manipura to the pancreas, Anahata to the thymus, Vishuddha to the thyroid, Ajna to the pituitary, and Sahasrara to the pineal. Leadbeater's own writing does not spell out this exact list in the form now repeated; it was filled in and standardised by later twentieth-century authors building on his general claim that the chakras correspond to glands, a claim that has no basis in the Sanskrit sources and, unlike the glands themselves, cannot be located or examined.