Renseignements généraux

Nº de série

S/O

Nº de partie

1

Nombre total de parties

1

Ou

S/O

Brevets

S/O

Description générale

metal casing, stand, scale holder, wiring, parts/ glass window/ cardboard scale

Dimensions

Remarque : Cette information reflète la taille générale pour l’entreposage et ne représente pas nécessairement les véritables dimensions de l’objet.

Longueur

20,0 cm

Largeur

13,8 cm

Hauteur

25,3 cm

Épaisseur

S/O

Poids

S/O

Diamètre

S/O

Volume

S/O

Lexique

Groupe

Physique

Catégorie

Équipement de démonstration et d'enseignement

Sous-catégorie

S/O

Fabricant

Ou

Welch

Pays

United States of America

État/province

Illinois

Ville

Chicago

Contexte

Pays

Canada

État/province

Ontario

Période

early 20th century

Canada

This piece of equipment was used at the Chatham Collegiate Institute in Chatham, Ontario, a secondary school which was founded in 1885 and closed in 2003. In 1851 the first school was established in the village of Chatham and by the late 1870's it was called Chatham High School. In 1885 the school attained the status of a collegiate institute, enabling it to obtain larger provincial grants and by 1887 a new school building had been constructed and the CCI was considered to be one of the most outstanding secondary schools in Ontario (it was destroyed by fire in 1946). In 1940 a new building was completed & again was considered to be one of the most modern educational facilities in the province. The school was closed in 2003.

Fonction

An instrument for detecting the existence & determining the strength of small electric currents, in this case to demonstrate principles of electricity in a school.

Technique

A small, self contained D'Arsonval galvanometer designed for general laboratory use, available in the 1927, 1928 & 1949 Welch catalogues. The instrument consists of an upright, glass-fronted metal box. On either side are the poles of the permanent magnet used to set up the constant magnetic field used to provide the torque on the current-carrying coil. The coil is suspended from the top of the box by a thin phosphor-bronze strip, with the lower suspension being a loose coil of the same material. The reverse side of the curved strip mounted at the end of the long foot carries a scale with reverse-printed numbers. The user looks through the rectangular aperture mounted above the curved strip, and sees the scale in the small mirror attached to the coil. To keep the eye fixed in the same position, the image of the centre line reflected from a small mirror on the surface of the glass cover is always kept in coincidence with the centre line observed in the rotating mirror (Ref. 3).

Notes sur la région

Inconnu

Détails

Marques

black lettering on scale reads "W.M. WELCH SCIENTIFIC COMPANY/ CHICAGO, ILLINOIS"/ black & red scale markings

Manque

appears complete

Fini

black wrinkle finish on casing/ colourless transparent glass/ glossy black painted base/ flat black painted parts/ metallic & copper coloured parts/ white scale

Décoration

S/O