There’s a probably apocryphal story about a noted physicist - he varies from story to story, but in the version I heard it was Max Planck - who in a test at school was asked how he would use a barometer to measure the height of a building. He answered that he would drop it off the roof and measure the time it took to hit the ground, and was failed on the question by the teacher, who told him not to play silly buggers but answer the question properly. Whereupon Planck provided a list of completely different but viable methods of measuring the height of a building with a barometer, including using it as a pendulum and measuring the time and amplitude of the swing; and offering it to the building owner as a bribe to tell him how high the building was. Then, he concluded, if he was really unimaginative, he supposed he could use it to measure the differences in air pressure on the ground floor and the roof.