Optical Range Finder

Physics

Accession Number: 2009.ph.272

Instrument Name: Optical Range Finder

Description:

The first piece, 2009,ph.272.1, consists of a metal tube coated in canvas and painted dark green. This cylinder is closed at both ends with what appear to be caps that are ringed by suede cushions. In one side of each cap there is a round glass window framed with black plastic. A leather strap is affixed to each of these caps, though both straps are broken and worn. Leather straps are also fixed around the base of each cap and fixed closed with orange-painted rivets, though these are also broken. In the centre of the tube is an adjustable eyepiece marked with a numerical scale around its outside ring, and beneath it is a fragment of a leather strap riveted to the tube body. To one side is a small glass window that shows a marked scale, and on this same side is a textured adjusting dial. On the other side of the tube is a metal screwed-on cap, which opens to reveal three small holes. The whole piece is set on two wooden supports 2009.ph.272.2 and 2009.ph.272.3. Each support has a semicircular cutout in which an end of the tube may rest, padded with felt. A paper label is affixed to the base of one of these supports.

Primary Materials:

Metal, leather, fabric, padding, canvas, paint, metal, glass, wood, felt, plastic

Markings:

On the textured dial: “HALVING ADJUSTER”. The small window scale is marked with numbers. The scale on the eyepiece is marked with numbers -4 to 4. Above the eyepiece, the tube is etched: “No 978 Bausch and Lomb Optical Co Rochester, NY”. On the label on 2009.ph.272.3: “This instrument must NOT be removed from the laboratory without permission.”

Dimensions (cm):

For 2009.ph.272.1: Length= 90, Diameter= 13. For 2009.ph.272.2 and 220.ph.272.3: Height= 24.5, Width= 30.5, Length= 23.

Function:

This piece was used to determine distance of the instrument from far-away objects.

Condition:

Good to Fair. The leather straps are all broken and worn, with sections missing. The padded rings around the caps are worn. The plastic around the eyepiece in the centre is broken, cracked, and brittle. The whole body exhibits scratches and abrasions, and the supports are chipped and scratched. The paper label is faded and torn.

Manufacturer: Bausch and Lomb

Date of Manufacture: c. 1920

Provenance:

University of Toronto Physics Department

Donated to UTSIC: Yes