Accession Number: 2009.ph.93
This is a large, flat and circular metal disk punched around the rim (within 5.5cm of the edges) with circular holes arranged in 5 unevenly space rings. There is also a punched hole in the centre of the disk; this has a small rounded notch in its edge. There are fine circular scratches on the disk; these are centered on the middle hole, as if it has been turned against another surface.
Primary Materials: Metal: Copper Alloy?
Dimensions (cm): Diameter = 23.5, Width =0.1
Good: The surface of the metal has been coated and this is in good condition aside from fine circular scratches that appear on both sides of the disk. These are more marked on one side than on the other.
Associated Instruments: 2009.ph.92, 2009.ph.94
Manufacturer: Locally made?
Date of Manufacture: 20th Century
University of Toronto Department of Physics