General Information

Serial #

N/A

Part Number

1

Total Parts

3

AKA

N/A

Patents

N/A

General Description

METAL & GLASS/ WOOD CASE WITH METAL HARDWARE, LEATHER HANDLE & FELT LINING

Dimensions

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

Length

20.0 cm

Width

15.5 cm

Height

14.0 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Exploration and Survey

Category

Photogrammetry

Sub-Category

N/A

Manufacturer

AKA

Pritchard Andrews

Country

Canada

State/Province

Ontario

City

Ottawa

Context

Country

Canada

State/Province

Unknown

Period

1940'S

Canada

DEVELOPED BY THE DOMINION FOREST SERVICE OF THE DEPT. OF MINES & RESOURCES IN OTTAWA. FURTHER DEVELOPMENT GAVE RISE TO THE SEELYSCOPE BUT NONE OF THE DEVICES BECAME WIDELY USED.

Function

USED TO 'SUPERIMPOSE' AN AERIAL PHOTO ON TO A MAP IN SUCH A MANNER THAT BOTH HAVE THE SAME HORIZONTAL SCALE. DETAILS FROM THE PHOTO CAN BE TRACED ON TO THE MAP QUICKLY AND EASILY.

Technical

ALLOWS A PHOTO TO APPEAR SUPERIMPOSED & PROPERLY ADJUSTED ON A MAP, PERMITTING DIRECT TRANSFER & PREVENTING ERRORS BY MAKING POSSIBLE A SIMULTANEOUS & NATURAL OBSERVATION OF THE PHOTO & THE ACTUAL MAP SHEET. THE SIMPLICITY OF THE OPERATION RESULTS IN AN ACCELERATION IN THE RATE OF PLOTTING.

Area Notes

Unknown

Details

Markings

PLATE: 'CAN. PAT. 392431/ US PAT 2229424/ MFD BY/ PRITCHARD-ANDREWS CO/ OTTAWA'/ PAPERS ATTACHED TO INSIDE BOX LID: 'D-1/ DUOSCOPE with binoculars (on 7 1/4 " centres)/ consisting of the following:/ 1 centre assembly with binoculars/ 2 large mirrors, 6 1/4 x 7 1/4/ 2 pr. of legs/ 2 glow-motion adjustment attachments/ 1 wooden carrying case/ 2 bars'/ 'WARNING/ THE MIRRORING OF THIS DUOSCOPE IS ON THE/ FRONT SURFACE OF THE GLASS./ PREVENT INJURY BY WIPING WITH CLEAN SOFT/ MATERIAL ONLY. MOISTEN WITH ALCOHOL IF/ NECESSARY'/ 'D1' SCRATCHED ON/ HANDWRITTEN IN RED ON CASE OUTSIDE: 'DUOSCOPE/(BINOCULARS)'

Missing

2 MIRRORS, 6 1/4 X 7 1/4 IN/ 2 PR OF LEGS/ 2 BARS

Finish

BLACK WRINKLE FINISH/ CASE - BLACK GLOSSY PAINT, GREEN FELT, BLACK HANDLE

Decoration

N/A