The nine choirs are arranged in Three Celestial Hierarchies with three
choirs in each
hierarchy:
Left Three,
2nd order:
Powers (chain), Virtues (spear), Dominations (crown)
Central Three, 1st order: Thrones (supporting posture), Seraphim
(flame-like), Cherubim (adoring posture)
Right Three, 3rd order: Principalities (trumpet), Archangels
(announcing), Angels (messengers to earth -downward thrust)
Medieval angelology source: Celestial Hierarchy by Dionysius the Areopagyte, ca. 500 AD
Celestial Choirs, Oxidized copper, about 4 feet tall. Full length about 30
feet, 1956. Courtyard wall with reflecting pool.