General Information

Serial #

11161 (base)

Part Number

1

Total Parts

4

AKA

telescope base (.1)

Patents

N/A

General Description

PRIMARILY BRASS; VERTICAL CIRCLE & VERNIERS GRADUATED ON SILVER. GLASS TUBE LEVELS & OPTICS. CELLULOID SHADES ON READING MICROSCOPE EYEPIECES OVER VERTICAL CIRCLE..1PT &.2PT CASES MADE OF WOOD. CIRCLE ON LEVELLING LEG ON.1 BASE MAY BE DIVIDED ON PLATINUM

Dimensions

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

Length

66.5 cm

Width

36.0 cm

Height

42.5 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Exploration and Survey

Category

Measurement-angles

Sub-Category

N/A

Manufacturer

AKA

HEYDE

Country

Germany

State/Province

Unknown

City

Dresden

Context

Country

Canada

State/Province

Unknown

Period

THIS TYPE OF INSTRUMENT USED C.1910+. THIS INSTRUMENT PROBABLY USED C.1915-1960S.

Canada

ORIGINALLY PURCHASED C.1915 BY DOMINION OBSERVATORY, ALONG WITH TWO OTHER ASTRONOMICAL TRANSITS. AS A HIGHLY PRECISE, PORTABLE TRANSIT INSTRUMENT IT WAS PROBABLY USED ON MANY SURVEYS BY GEOLOGICAL SURVEY OF CANADA (GSC), TO WHOM IT WAS LOANED. IT CONTINUED TO BE USED BY GEODETIC SURVEY IN THE 1960S.

Function

TO DETERMINE TIME, LATITUDE, LONGITUDE & AZIMUTH IN ORDER TO ESTABLISH REFERENCE POINTS IN TRIANGULATION SURVEYS.

Technical

THIS TYPE OF PORTABLE TRANSIT INSTRUMENT IS KNOWN AS THE BROKEN-TELESCOPE TRANSIT: THE LIGHT WHICH PASSES THROUGH THE OBJECT GLASS IS REFLECTED THROUGH A RIGHT ANGLE BY MEANS OF A PRISM PLACED IN THE TRUNNION AXIS. AN EYE PIECE IS FITTED AT ONE END OF THE HOLLOW AXIS & A LAMP AT THE OTHER. BECAUSE OF THIS OPTICAL DESIGN THE STANDARDS CAN BE MADE LOWER AND THE INSTRUMENT MORE COMPACT (REF.3,P.62).

Area Notes

Unknown

Details

Markings

.1 PLATE ON BASE READS: 'Gustav Heyde/ G.m.b.H./ Dresden- N 23/ Nr. 11141'. EMR INVENTORY LABEL READS: 'EMR/ INVENTORY CONTROL-/ R.C./ EQ. CODE/ 633 024610/ 5825-66-666-6666/ DO NOT REMOVE'- FRENCH TEXT ALSO PRESENT. LEVELLING LEG CIRCLE GRADUATED 0-99 BY SINGLE INCREMENTS. TUBE LEVEL GRADUATED BUT NOT LABELLED/ PAPER LABEL ON CASE TOP READS: "ASTRONOMICAL/ INSTRUMENTS/ WITH CARE". Second label stapled to tops printed, with some handwriten text: "2 PACKAGES/ IN THIS SHIPMENT./ TO THE STOREKEEPER,/ GEODETIC SURVEY OF CANADA,/ OTTAWA, ONT./ Via P.W.A. AIRFREIGHT [TO ED]MONTON/ CN EXPRESS TO [OTT]AWA/ From/ Chief of Party/ LESLIE F. GREGERSON/ GEODETIC SURVEY PARTY"./ "# 208" HANDWRITTEN IN BLACK MARKER ON INSIDE OF LID OF CASE.

Missing

UNKNOWN

Finish

.1 BASE: FINISH IS ORIGINAL BLACK ENAMEL; ADJUSTMENT KNOBS & SOME FITTINGS NICKEL-PLATED; BLACK SYNTHETIC KNOB ON AXIS LEVER; SILVER METAL LEVELLING LEG. TUBE LEVEL (NOT ORIGINAL) HAS GREY ENAMEL CASING/ .1PT- CASE: WOODEN CASE, PAINTED WHITE

Decoration

N/A