Table of contents : 01 Pioneers of Precision 02 Standards of length I: Early Standards 03 Standards of Length II: Modern Standards 04 Societe Genevoise 05 Johansson 06 The National Physical Laboratory 07 The NPL from 1918 08 Taylor, Taylor and Hobson 09 Carl Zeiss of Jena 10 Other Personalities and Companies 11 Mechanical Measurements 12 British Optical Instruments 13 Design, Standards, and Calibration 14 Modern Metrology