The supports are used in optical studies: on one of them the tuning fork is placed horizontally and on the others vertically.
On the U-shaped wooden base, which is made of boards fifteen centimetres wide, the front board is 103 cm long and the two side pieces measure 39.6 cm.
It is used in the graphic study and the two forks required, both horizontal, can be arranged longitudinally, with the prongs facing each other, for the study of the composition of vibrations that are parallel or rotated by 45 degrees, one in one direction and the other in the opposite direction with respect to the front board of the base, in the study of the composition of orthogonal vibrations.