William Roy’s standard scale, 1742
42-inch standard scale marked with a standard yard, made by Jonathan Sisson and divided in 1742 by John Bird, both based in the Strand, London. The scale was owned by surveyor General William Roy and used by him whilst conducting measurements of a baseline at Hounslow Heath in 1784.
- Measurements:
-
Overall: 14 mm x 1090 mm x 7 mm, 0.74 kg
- Materials:
- brass (copper, zinc alloy)
- Object Number:
- 1931-988 Pt1
- type:
- linear measure standard