Compressing fountain

The fountain was bought by Giovanni Poleni for the Cabinet of Physics of Padua University between 5 August 1753 and 18 August 1755.

Date: 3rd quarter 18th century

Description

Poleni catalogued this instrument in his Indice delle Macchine as a “Compressing fountain, made of a large copper vessel with a brass base, 15 inches high, and a nozzle 18 inches long, with a key or cock also made of brass; and a syringe 14 inches long, also in brass […]. It serves for the experiment of the compression and elasticity of air”.

A brass tube is inserted through the neck of the vessel. It bears a cock at its upper side, while its lower side is open and almost touches the bottom of the container. To use the fountain, the copper vessel was two-third filled with water, and a compression pump was fixed at the top of the tube. Thanks to this pump, the air contained above the water could be little by little compressed. The cock was then closed and the pump removed. If the cock was opened again, the water started jetting above the fountain, due to the action of the compressed air.


Materials and techniques: copper/brass/wood

Dimensions: height 94 cm, diameter 27 cm

Related scholars: Giovanni Poleni (b.1683 - d.1761). Professor of Experimental Philosophy at the University of Padua from 1739 to 1761.

Keywords: mechanics, pneumatics

University of Padua, Museum of the History of Physics

Cat. Number: 85

Exhibitions

  • "Bagliori nel vuoto. Dall'uovo elettrico ai raggi X: electricity e pneumatica dal Seicento ad oggi", Padova, Botanical garden, 1 February-30 June 2004

Bibliography

  • Joseph Théophile Desaguliers, Cours de physique expérimentale, 2 vols., Paris, 1751
  • Jean Antoine Nollet, Leçons de physique expérimentale, 6 vols., Paris, 1st ed., 1743-1764
  • Giovanni Poleni, Indice delle macchine, Biblioteca Nazionale Marciana di Venezia, mss.it., cl. III, 54-55 = 4969-4970, cl. IV, 626 = 5488, 636 = 5497 [It was written by Giovanni Poleni from 1740 to 1761]