On a white marble base, two Vestal Virgins tend a flame that honors the goddess of the hearth, Vesta. A drawing still exists that shows the clock was designed to sit on a mantelpiece, its classical theme a suitable reference to the fireplace below. The altar that houses the clock's movement is fitted with horizontal enameled and jeweled hour and minute rings, while a sacrificial procession underneath is shown in gilt bronze. A branch of roses draped over the edge of the altar points to the time.

Henri-François Dubuisson made the clock's dials.