It is a compressed-air rotating apparatus for disks, with a horizontal axis.
The vertical brass tube through which the jet of air passes to cause the apparatus to rotate is fixed, by means of a cursor, to a horizontal wooden guide 9 cm long placed at the centre of a heavy, square base (16.5 x 16.5 x 5 cm in height), it too made of wood, parallel to two of the sides.
A horizontal appendix, near the support, allows connection of the tube to a compression pump or to a compressed-air bottle by means of a rubber joint.
The tube can be lengthened to bring the axis of rotation to a height between 22.5 and 29.5 cm above the supporting plane.
The upper part of the tube slides inside the lower part, ends at the top in the form of a flute mouthpiece flattened parallel to the axis of rotation, which is supported by a rectangular brass frame soldered to the end of the tube. ...continues