6" bellmetal rule engraved "Joseph Whitworth, Manc

Made:
1850 in Manchester
maker:
Joseph Whitworth

6" bellmetal rule engraved "Joseph Whitworth, Manchester, standard at 62 degree fahrenheit," part graduated to 64ths, c 1850

The bell-metal rule by Joseph Whitworth, Manchester, reflects his insistence on accuracy, being marked 'standard at 62 'Faht’. It is marked in fractions of an inch rather than decimal parts; measurement in decimal inches was strongly advocated by Whitworth.

Details

Category:
Industrial Metrology
Object Number:
1987-749
type:
rule
credit:
Christie's South Kensington Limited