A wooden box with a hinged lid. On the side of the wooden box there is a 13 cm by 3 cm bakelite plaque with 4 terminals. The two left-most terminals are marked with “6 VOLTS” and the two right-most terminals are marked with “GA”. On the front of the wooden box there is a viewing window with a scale from 20-0-20, with a corresponding handwritten scale 0-50. Inside the wooden box there is a light source, lens, magnet and a mirror marked with “LEEDS & NORTHRUP CO., PHILADELPHIA”, and “CAT. NO. & COIL RES.”
Accession Number: 2009.ph.202
Primary Materials: Wood, Metal, Glass
Old inventory number = phy354. On top of the lid there is a label “LEEDS & NORTHRUP CO.”, “PHILADELPHIA PENNSYLVANIA”, “MADE IN U.S.A.”, “CAT. NO. 2420C”, and “SERIAL NO. 616616”. Inside the wooden box there is a mirror marked with “LEEDS & NORTHRUP CO., PHILADELPHIA”, and “CAT. NO. & COIL RES.”
Height = 13 cm, Length = 21 cm, Width = 13.5 cm
For making precision measurements of electric current.
Leeds and Northrup, Philadelphia, Pennsylvania, USA
Date of Manufacture: Mid twentieth century
This artifact was part of a collection of electrical instruments (mostly brass electrometers and ballistic galvanometers) gathered by University of Toronto Professor of Physics Martin J.G. Lee (d. 2009). These were likely acquired from Dr. Lee’s office c. 2010 or 2011.
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