General Information

Serial #

3788

Part Number

1

Total Parts

2

AKA

N/A

Patents

N/A

General Description

METAL (INCLUDING BRASS & POSSIBLY COPPER), CERAMIC, SYNTHETIC & GLASS COMPOSITION. SILK SUSPENSION THREAD. (Needle is suspended by a .002" diam. non-ferrous wire - T. Missio, Aug. 2010.)

Dimensions

Note: These reflect the general size for storage and are not necessarily representative of the object's true dimensions.

Length

22.0 cm

Width

19.0 cm

Height

30.5 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Physics

Category

Demonstration & teaching equipment

Sub-Category

N/A

Manufacturer

AKA

Carpentier

Country

France

State/Province

Unknown

City

Paris

Context

Country

Canada

State/Province

Ontario

Period

PROBABLY USED C. 1890S- 1920.

Canada

PART OF A COLLECTION OF PHYSICS LABORATORY AND CLASSROOM DEMONSTRATION APPARATUS FROM MCMASTER UNIVERSITY. FOUNDED IN 1887 MCMASTER WAS ORIGINALLY A BAPTIST INSTITUTION, AND WAS LOCATED IN TORONTO. IN 1930 THE UNIVERSITY AND ITS STUDENT POPULATION OF 500 WAS MOVED TO HAMILTON, ONT. (REF. 1)

Function

TO MEASURE A SMALL ELECTRIC CURRENT.

Technical

ASTATIC GALVANOMETER WITH DUAL MAGNET COMPENSATION, ORIGINALLY DESIGNED BY NOBILI (C. 1825-30) AND POPULARIZED BY H.D.RUHMKORFF. THIS EXAMPLE BY JULES CARPENTIER WHO WORKED FOR, THEN SUCCEEDED, RUHMKORFF. (REF. 1) TERM ASTATIC INDICATES A NEGATIVE RESTORING FORCE HAS BEEN APPLIED TO ENHANCE ANY DEFLECTING FORCE, THUS MAKING THE INSTRUMENT HIGHLY SENSITIVE.

Area Notes

Unknown

Details

Markings

.1 " Ateliers Ruhmkorff/ J. Carpentier. Engr. Constr. Paris " incised on lower half of divided circle. Scale 90-0-90 divided by single increments incised on upper half of circle. " 3788- [?] " stamped into terminal block/.2 no markings.

Missing

NONE. From CA of 11/29/2001 by Matthew Bruce: No - appears complete

Finish

.1 SOME LACQUERED BRASS SURFACES. COILS MOUNTED ON CERAMIC BLOCK. SYNTHETIC BLOCK FORMS TERMINAL MOUNTING. COPPER COLOURED METAL DISK FORMS CENTRE OF DIVIDED CIRCLE. INDICATOR NEEDLE SUSPENDED OVER CIRCLE BY MEANS OF SILK THREAD/.2 LACQUERED BRASS FRAME SUPPORTS GLASS COVER.

Decoration

N/A