Precision made possible the industrial age.
In preindustrial times only occasional advances were made such as the first measurement standard the “iron ulna” or yard stick and standardized divisions of yard to foot to inch. The ability to measure accurately paved the way for mass production which, in turn, was to raise the standard of living for everyone. Through specialization, and the use of precision gages, work-men became so adept at their jobs and did such accurate work that manufactured goods could be assembled without time-consuming filing and hand fitting. Once the relationship between measurements, interchangeability and mass production was fully appreciated, factories began an outpouring of products reducing cost and increasing consumer demand. As the nineteenth century drew to a close, new improvements such as Johansson blocks and optical flats brought measurement to the millionth of an inch; yet even today, many manufacturers use plug gages and “go” – “no go” gages for their daily quality controls. With the most recent technology it is now fully feasible to perform in-process, non-contact gaging at the micron and sub-micron level, perhaps spurring a new American manufacturing revolution.