The instrument was bought by Giovanni Poleni for the Cabinet of Physics of Padua University between 16 September 1758 and 12 September 1760.

Date: 3rd quarter 18th century


A square frame is mounted at the top of a wooden stand and houses a convergent lens (the original lens was lost and replaced). A plane mirror is inserted in a second frame, the angle of which can be adjusted. The pictures to be observed were placed at the basis of the device, reflected through the mirror and enlarged by the lens. The original figures that accompanied the instrument are lost.

The instrument was catalogued by Giovanni Poleni in his Indice delle Macchine as “A device made of a basis and a small frame holding a plane mirror, which forms an angle of 45 degrees. There is also a crystal lens 4 inches of diameter. There are 12 drawn papers to be used with this instrument as well. All this serves for an optical observation”.

Materials and techniques: glass/wood/speculum

Dimensions: height 65 cm, width 24 cm, length 24 cm

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

Keywords: optics, pre-cinema

University of Padua, Museum of the History of Physics

Cat. Number: 92


  • 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]