Unknown Optical Attachments

Astronomy

Accession Number: 2018.ast.88.1-2

Description:

These are two small identical lens-like objects. They are small cylindrical brass pieces with a circular glass window in one end; the other end is open. There is a small threaded hole through the brass cylinder about a quarter of the way down the cylinder from the end fitted with glass.

On the glass window there are small etched shapes. Each of these consists of a small open circle, a line, and then another open circle. On 2018.ast.88.1, the central line is longer, on 2018.ast.88.2, the central line is shorter. Marks on the brass rim around the glass, apparently added by a user, indicate the horizon of the straight lines.

Primary Materials: Metal: Copper Alloy, Glass

Markings: None.

Dimensions (cm): Length = 2.1, Diameter, 2.3

Function: Unknown

Condition:

Very good: These pieces are part of some larger piece of equipment. Their metal surfaces are corroded.

Date of Manufacture: Early 20th Century

Provenance:

This object was likely moved from the David Dunlap Observatory in Richmond Hill in 2008, upon the sale of the observatory. It was stored at the Department of Astronomy and Astrophysics until 2017, when it was moved to a new storage location in McLennan Physical Laboratories.