Pump with two unusually large barrels secured to a wooden table. A metal frame mounted on a pillar supports the toothed balance mechanism that operated the two rack-and-pinion mechanisms of the pistons. The pump plate, which serves as a bell-jar plate, is attached to the table by means of a special fitting. A large double-handled stop-cock connected the bell-jar to the barrels. The handles—originally attached to the central axle of the balance mechanism—are missing, as is the pipe-work under the table. Provenance: Lorraine collections.