[Read!] Machinery's Reference Series "measuring Tools"

Nels, that was strange? I didn’t see any reference to using your thumb or eye ball technique?...Dave
 
A fascinating book Nels. Thanks for sharing!

I read the first chapter over breakfast. As a physicist, I have always been keenly interested in measurements and measurement standards. Accurate and reproducible standards were indeed a serious problem back in 1910 when the book was written. Now days, being able to measure a length to 12 decimal places seems commonplace.
When in London last year, I took some photos of the length standards embedded in the masonry work in Trafalgar Square. This is the start of the chain standard used by surveyors, set in place in 1876. Apparently, tradesmen and craftsmen would visit them the compare their own standards. There are much better photos to be found by googling "length standard Trafalgar Square"
Chain Std  .JPG Length Std  .JPG
 
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