(from ἀρχή, the principal, chief, or first mover); a sort of primum mobile set up by Helmont, to superintend the animal economy, and preserve it. It is akin to Plato's anima mundi.—Hippocrates uses the words ἀρχαῖον πνεῦμα, to signify the former healthy state before the attack of the disease.

ARCHACOLYTHUS (from ἀρχάς, chief, and λόγος, minister), an ancient dignity in cathedral churches: the ministers whereof were divided into four orders or degrees, viz. priests, deacons, subdeacons, and acolythi; each of which had their chiefs. The chief of the acolythi was called archacolhythus.