Renseignements généraux

Nº de série

S/O

Nº de partie

2

Nombre total de parties

4

Ou

S/O

Brevets

S/O

Description générale

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

Remarque : Cette information reflète la taille générale pour l’entreposage et ne représente pas nécessairement les véritables dimensions de l’objet.

Longueur

57,0 cm

Largeur

33,0 cm

Hauteur

33,0 cm

Épaisseur

S/O

Poids

S/O

Diamètre

S/O

Volume

S/O

Lexique

Groupe

Exploration et levé

Catégorie

Mesure-angle

Sous-catégorie

S/O

Fabricant

Ou

HEYDE

Pays

Allemagne

État/province

Inconnu

Ville

Dresde

Contexte

Pays

Canada

État/province

Inconnu

Période

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.

Fonction

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

Technique

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).

Notes sur la région

Inconnu

Détails

Marques

TRANSIT TELESCOPE BEARS EMR INVENTORY LABEL: IDENTICAL TO .1 EXCEPT EQ. NO. '633 024618/ 6675-66-666-6665'. VERTICAL CIRCLE DIVIDED 0-360 AT 15-MINUTE INTERVALS: READ BY VERNIER DIVIDED 0-20 AT 30-SECOND INTERVALS. TUBE LEVEL ON CIRCLE GRADUATED BUT NOT LABELLED./ .2PT- CASE: WOODEN CASE, PAINTED WHITE. 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.

Manque

TRANSIT INSTRUMENT APPEARS TO HAVE BEEN REFINISHED AND PROBABLY ALTERED FOR USE BY GSC INTO 1960S.

Fini

HAS LIGHT & MEDIUM GREY ENAMEL FINISH (NOT ORIGINAL); GREEN ENAMEL FINISH ON COUNTERWEIGHTS. ADJUSTMENT KNOBS & SOME COMPONENT PIECES ARE NICKEL-PLATED. OFF-WHITE CELLULOID SHADES: READING EYEPIECES ARE BLACK WITH BRASS TUBES/ .2PT- CASE: WOODEN CASE, PAINTED WHITE.

Décoration

S/O