General Information

Serial #

P-145

Part Number

1

Total Parts

15

AKA

N/A

Patents

N/A

General Description

WOOD BASE; METAL & SYNTHETIC MECHANISM & PARTS; SYNTHETIC MECHANISM COVER

Dimensions

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

Length

22.9 cm

Width

12.7 cm

Height

23.5 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Metrology

Category

Length

Sub-Category

N/A

Manufacturer

AKA

American Instrument

Country

United States of America

State/Province

Minnesota

City

Silver Springs

Context

Country

Canada

State/Province

Unknown

Period

1940'S +

Canada

THIS INSTRUMENT WAS ACQUIRED BY MR. MACLATCHY SECOND HAND FOR HIS OWN USE IN 1970S BUT HE USED IT INFREQUENTLY. IT WAS MADE IN 1944 & APPEARS TO HAVE BEEN RECALIBRATED IN 1953 FOR RCA VICTOR INMONTREAL.

Function

INSTRUMENT WHICH MEASURES THICKNESS OF DEPOSITED COATINGS ON METAL SAMPLES BY USING SEVERAL CALIBRATED REFERENCE MAGNETS. MAGNET IS PLACED IN CONTACT WITH SURFACE & FINE WIRE IS ATTACHED TO BEAM OF SCALE. DIAL IS ROTATED UNTIL MAGNET BREAKS FROM SURFACE - FORCE REQUIRED TO BREAK BOD INDICATES THICKNESS.

Technical

LITTLE IS KNOWN ABOUT ORIGINS OF DEVICE THOUGH ADVANCES IN PLATING METHODS & TECHNOLOGIES CLEARLY MADE IT USEFUL. MILITARY SPECS WOULD HAVE ROUTINELY REQUIRED SPECIFICATION OF THICKNESSES OF PROTECTIVE COATINGS & THINNESS OF THESE MADE STANDARD MICROMETERS INEFFECTIVE - HENCE USE OF CALIBRATED MAGNETS TO DETERMINE CHANGE*

Area Notes

Unknown

Details

Markings

SILVER LETTERING ON DIAL READS "AMINCO-BRENNER/ MAGNE-GAGE/ AMERICAN INSTRUMENT CO./ SILVER SPRING, MARYLAND"; INCISED WHITE "P-145"; MOULDED "AMINCO" IN PLASTIC CASING

Missing

.15 CARRYING HANDLE OR STRAP

Finish

BLACK BASE; METALLIC & PLATED PARTS; BLACK PAINTED DIAL & PARTS; BLACK SYNTHETIC KNOB & PARTS; TRANSPARENT MECHANISM COVER.

Decoration

N/A