Eole. Aeolus was the god of the Winds, which he kept fastened up in a bag.
fausse clef, skeleton key.
fatal, 'charged with destiny.'
pesanteur. Not 'weight' but 'the force of gravity'.
Nadir is the point in the heavens which would be reached if a line were drawn through the centre of the earth and carried on till it reached the sky. But here it seems to be used loosely for any distant point in the heavens. The meaning is that from a remote distance the round earth, as it came into view beneath the ship, would have the appearance of a dusky comet.
aéroscaphe. A word once proposed, but never widely accepted, as a designation for an airship. It is derived from the Greek aer (air) and skaphe (a vessel).
humaine, i.e. made by man.
treuil, 'windlass.'
moufle, 'block.'
moteur, 'driving power.'