General Information

Serial #

N/A

Part Number

7

Total Parts

16

AKA

glass scale

Patents

N/A

General Description

clear glass

Dimensions

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

Length

22.5 cm

Width

2.1 cm

Height

N/A

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

Wild

Country

Switzerland

State/Province

Unknown

City

Unknown

Context

Country

Canada

State/Province

Ontario

Period

presumably c. late 1960s- early 1990s.

Canada

Accessory for Wild A8 plotter With the exception of the Wild A10 [few of which were used in Canada], this machine was the most sophisticated plotter available before digital technology.

Function

To establish the plotting scale to be used when mapping.

Technical

Example of precisely ruled glass scale of type used with photogrammetric plotter. Scales are inserted in a holder directly attached to the z column and projected under strong magnification onto a ground glass screen in front of the operator. [Ref.3, p.17] The rule [glass scale] must correspond to the model scale [instrument scale] in order to enable the operator to read the elevations. Wild provided a set of 4 tables, one for each of the 4 different groups of rules [glass scales] available, to facilitate the selection of the appropriate rule and [ratio] gear for a given plotting scale. [Ref. 2, p.32] This scale would have been part of Group II scale set: it is housed with assorted scales from various scale sets.

Area Notes

Unknown

Details

Markings

"1: 20000/ feet" and scale etched into glass. Handwritten markings on one short end of rule are illegible.

Missing

None: scale is complete in itself.

Finish

Clear glass rule bears black markings.

Decoration

N/A