Precise measurement has long been a key to progress, say Dr Russell Miller and Dr David Whittaker of the National Physical Laboratory. “Medieval seafarers used lodestones for navigation, relying on magnetic properties that we now know arise from quantum effects, long before attempts were made to understand the underlying science in the 19th century.”

And quantum effects, they note, underpin much of modern technology today. “They’re used everywhere from the semiconductor chips in everyday mobile phones and computers to the atomic clocks that provide precise timing for telecommunications and banking systems. The first atomic clock was actually developed at NPL.”

They tell the story of advances in precision measurement which have opened the way to remarkable achievements in science, technology and industry, and they demonstrate examples of cutting-edge measurement techniques.

The National Physical Laboratory (NPL) was founded 125 years ago as the UK’s national measurement institute.