06/19/2023
Hundreds of years later, we still measure pressure – whether you’re pumping up a tire or travelling in the air – in terms of pascals or kilopascals (1,000 pascals).
The unit was named for Blaise Pascal, a 17th century mathematician and scientist. You may have noticed different air pressure at different levels if you’ve had your ears pop on takeoff or landing on a plane. That’s one practical example of Pascal’s studies.
And he had a strange way of testing his theory.
Pascal thought if you traveled up a mountain, you’d find less air pressure because there’s less air to press down than lower in the atmosphere.
He wasn’t healthy enough to try this himself, but he convinced his brother-in-law to carry out the experiment for him – using mercury in a bowl. As expected, the mercury varied as his brother-in-law climbed up and down the mountain.
Disclaimer: We love an intrepid measurer here at NIST, but this is not something you should try at home!
Pascal’s 400th birthday is coming up next week. NO pressure, but if you’d like to learn more about him, check out our latest Taking Measure blog: https://www.nist.gov/blogs/taking-measure/under-pressure-blaise-pascal-barometer-and-bike-tires
