box of pieces of Sir William Thomson's quadrant electrometer
Date: 1854-1884
Inventory Number: 1997-1-0657b
Classification: Electrometer
Dimensions:box: 5.9 × 21 × 12 cm (2 5/16 × 8 1/4 × 4 3/4 in.)
Accessories: Extra parts contain; 38 components, 20 brass screws and a bag of metal cutouts.
Description:
This is a disassembled unit of Thomson's quadrant electrometer. For a description of the assembled instrument see No. 1997-1-0647.
This unit consists of a tall, hexagonal metal cage with a triangular base with three leveling screws and three diagonal beams that go from the leveling screws to the top edges of the hexagonal cage. The cage has a door that closes with a screw.
On top of the instrument, not secured, is the brass panel that holds the four quadrants as well as some of the control knobs. All other parts are currently stored in two cardboard boxes.
These parts include several brass pipes, binding posts, the parts for the semicircular panel, and at least four different small metal vanes. There are many components missing, and others are duplicated.
The small triangle indicates that the instrument was at the Jefferson Laboratory, Physics Department, Harvard University.