Tibetan Tsa Lung — Three Channels

Uma (dbu ma) — the central channel, running along the front of the spinal axis from the secret-place cakra at the perineal floor up to the crown aperture. In Tsongkhapa's presentation it is described as deep blue or indigo, hollow, four-fingers-wide internally, and ordinarily empty of wind and drops in unrealized practitioners. The completion-stage yogas of Naropa work to dissolve the winds of roma and kyangma into uma, an inner event whose phenomenology (the four blisses, the eight signs of dissolution) is the heart of the Six Yogas curriculum.

Roma (ro ma) — the right channel, red in colour, paralleling uma to its right and rejoining at the brow centre. In Vajrayana physiology it is the conduit of the red drop (thig le dmar po) inherited from the mother and — in the gendered iconography of completion-stage yoga — associated with prajñā (wisdom), the menstrual element, and the female principle. This gender-mapping is the inverse of the Hindu / Tantric piṅgalā: same side, same colour, but Hindu sources read piṅgalā as solar / male / dynamic. The two schemes are not to be blended.

Kyangma (rkyang ma) — the left channel, white in colour, paralleling uma to its left. Conduit of the white drop (thig le dkar po) inherited from the father; in the gendered iconography it is associated with upāya (skillful means), the seminal element, and the male principle. The inversion vs. Hindu nāḍī iconography (where iḍā = left = white = lunar = female) is precisely on the gender mapping: Tibetan Vajrayana keeps the same side and colour but reads the masculine / feminine attributions oppositely. The completion-stage practice draws the winds of both flanking channels into uma; the resulting union of red and white drops at the heart cakra is the somatic correlate of the union of wisdom and means.

The four-faced secret-place cakra (gsang ba'i 'khor lo) at the perineal floor — the point where the three channels are said to be knotted below and from which uma ascends along the front of the spinal axis. Lower terminus of the central channel in Tsongkhapa's presentation.

Cakra station on uma at the navel (the sixty-four-spoked site in the full enumeration). Rendered here as a trajectory waypoint of the central channel rather than a separate editorial entity; see the tsa_lung decision record for the channel-only Stage-1 scoping.

Cakra station on uma at the heart — the site where the red and white drops unite in completion-stage yoga, and the locus of the very subtle mind-and-wind that transmigrates at death. Trajectory waypoint of the central channel in this rendering.

Cakra station on uma at the throat (the sixteen-spoked site in the full enumeration). Rendered as a trajectory waypoint of the central channel.

The crown aperture (usnisa-kamala) at the vertex — upper terminus of uma in Tsongkhapa's presentation, and the egress point of the subtle mind-and-wind at the time of death in the transference (phowa) practices built on this channel map.

The brow-centre junction: roma, paralleling uma to its right, and kyangma, paralleling it to its left, curve back to the central axis and rejoin here before their terminal rise to the nostril region as described for the flanking channels in the Six Yogas presentations.

Lower trajectory anchor of Roma near the pelvic floor, offset to the right of the central axis. The flanking channels parallel uma from below the navel region upward; precise lower-end placement varies between illustrations and carries a wider uncertainty radius than the midline stations.

Navel-level trajectory waypoint of Roma. In completion-stage visualisations the two flanking channels bind around the central channel at the navel wheel; the waypoint marks the parallel path at this level, not a distinct editorial entity.

Heart-level trajectory waypoint of Roma. The completion-stage yogas draw the winds of both flanking channels into uma at the heart cakra; the station marks the parallel path approaching that junction level.

Throat-level trajectory waypoint of Roma as it rises toward the brow-centre rejoin. Curvature between this station and the brow is smoothed in rendering (path_rendering: smoothed_curve); the true path is textual, not dissected.

Lower trajectory anchor of Kyangma near the pelvic floor, offset to the left of the central axis. The flanking channels parallel uma from below the navel region upward; precise lower-end placement varies between illustrations and carries a wider uncertainty radius than the midline stations.

Navel-level trajectory waypoint of Kyangma. In completion-stage visualisations the two flanking channels bind around the central channel at the navel wheel; the waypoint marks the parallel path at this level, not a distinct editorial entity.

Heart-level trajectory waypoint of Kyangma. The completion-stage yogas draw the winds of both flanking channels into uma at the heart cakra; the station marks the parallel path approaching that junction level.

Throat-level trajectory waypoint of Kyangma as it rises toward the brow-centre rejoin. Curvature between this station and the brow is smoothed in rendering (path_rendering: smoothed_curve); the true path is textual, not dissected.