Graphometer

Struttura del meccanismo
Funzione	The graphometer comprises a brass semi-circle graduated from 0 to 180°. This limb is equipped with two sights, one fixed relative to the diameter and one mobile. The pinnules are small metal frames at the ends of the sights, each containing a metal wire. The mobile sight turns about the centre of the limb, enabling its graduations to be read. In the middle of the limb there is a compass, used for orientation. When in use, the graphometer was attached to a tripod (missing here). The attachment system is located on the rear of the graphometer and consists of a small sphere enclosed by two shells, tightened by a butterfly nut (ball and socket joint). The cylindrical shaft enables the device to be attached to the tripod.
Dimensione del meccanismo	planare
Movimento del movente	Rotazione
Moto del cedente	Rotazione

Applicazione
Esempi di applicazione	This instrument is used to measure angles in the horizontal plane. To use it, two distant objects are chosen and the instrument is placed at the apex of the angle, in a horizontal position. The first object is fixed by the sight; the second is fixed by the second, mobile sight. The number of degrees on the limb between the two sights is then read off. This device was used during class simulations or practical courses by future teachers at the men’s and women’s teacher training colleges of Aurillac (Cantal), now the IUFM (University Teacher Training Institute).

Permanent links

DMG-Lib		https://www.dmg-lib.org/dmglib/handler?mcdsc=2922025
Europeana		http://www.europeana.eu/portal/record/2020801/dmglib_handler_mcdsc_2922025.html