Wooden frame with a base and two lateral uprights supporting a mobile cross-piece fitted with a brass nozzle. To the bottom of this fitting were attached a vertical series of three bladders communicating with one another. The lowest carried a weight resting on the base of the machine. When air was pumped into the bladders, they dilated, raising the weight. The instrument, designed by Jean-Antoine Nollet, demonstrated that multiple small-scale phenomena can produce a noticeable effect. Provenance: Lorraine collections.