Well of Souls

The Well of Souls is the cave under the rock inside the Templum Domini ("Temple of the Lord") in Jerusalem.
The cave was regarded by Christians and Jews as the holy of holies during the era of the Crusaders, and Western iconography, such as the print by Salvatore and Giandomenico Marescandoli in 1600, portrayed Dome of the Rock (the Templum Domini) as the Temple of Solomon.
Templum Domini icon.

Several maps of Dome of the Rock revealed that the house is an octagon with a rock in the center. The rock is called foundation stone or pierced stone.

Although the Templum Domini isn't the only place God dwells, it serves as a physical reflection of heaven and God on his throne. The octahedral structure of the wall of the Templum Domini is a reflection of Bagua (heaven) and the rock is a reflection of the Tao enthroned on the eight trigrams.
Dome of the rock map.

Yin (the dark half of the Tao) is the rock and Yang is the Well of Souls inside the the pierced stone.

Since the holy of holies in Solomon's Temple was a cube, the Well of Souls is a cube inside an octahedron. The souls are spirits conveyed by Yang.

The octahedron with the cube is Yantra, the square and star symbol on the front cover of the Leningrad Codex. The octahedron is the wall of the Templum Domini and the star (the hexagram) is the pierced stone. The hexagon inside the hexagram is the Well of Souls.
Leningrad Codex carpet page.

Shri Yantra is the flower of the tree of life whose fruit is the cube known as the fruit of life. The hexagon is a cube, and revealing the cube from the hexagon is the fruit emerging from the flower.

The fruit emerging from the Yantra is life flowing out of the the Well.

The Well of Souls is the source of the river of life. The life is qi (ch'i) flowing out of heaven to every human and thing like a river.

Qi is the vital force reinvigorating the world and tilting humans and everything in the universe toward harmony, balance, well-being, good health, progress and sustainability. It creates a bright future, gives hope and  confidence for the future of humanity, and projects the world towards construction (building).

The well of souls is the hexagon in the square and star symbol on the Leningrad Codex carpet page. The hexagon is a dice, a cube with six square faces. The six faces are numbered from one to six with each face having a number of pips different from the remaining five faces.

The face with five pips is represented by a five-pointed star hanging from the small hole leading into the Well of Souls from the southeast corner of the foundation stone.

The five-pointed star represents the face with five pips, and there is a total of twenty one pips on the six faces of the dice (the well). The remaining sixteen pips are sixteen circles distributed round the star of the Leningrad Codex cover page.

Therefore, the five-pointed substitute of of the Leningrad Codex hexagram shown in the first diagram above is one of the six square faces of the dice; specifically, it the face with five pips.

Ba(Bagua) is animated as the Lo Shu magical Turtle in which the five-pointed star is 5 in the center of Lo Shu magic square.

Qi is Lo Shu river flowing from the Well of Souls. This means that the "river map" is the map of heaven reflected by the map Templum Domini.

Note that 5 is central to the magic square on the back of the Turtle as the five-pointed star lamp is hanging from a hole above the Well of Souls.

The cube is Rubik's cube. In 2-D, the cube (the Well of Souls) is Lo Shu square in which 5, representing the five-pointed star, is central to the remaining eight figures.

Each of the eight figures is a symbol, such that the eight figures are eight symbols surrounding 5.