Seventeenth-Century Barometer

Timeline

1. 1651–1654Europe · EuropeFollowing the foundational work of Torricelli (1643) and Pascal (1648 altitude-measurement experiments), the mercury barometer spread rapidly among European natural philosophers between 1651 and 1654, becoming a core instrument for studying atmospheric pressure and the nature of the vacuum; scientists in many countries began systematically recording pressure changes.
2. 1654Regensburg · German landsThe mayor of Magdeburg, Otto von Guericke, demonstrated the famous Magdeburg hemispheres experiment before the Imperial Diet of the Holy Roman Empire: two copper hemispheres, each pulled by 16 horses, could not be pulled apart after the air inside was evacuated, dramatically proving the enormous force of atmospheric pressure and greatly stimulating European scientific interest in the principle of the barometer.
3. 1659–1660Oxford · EnglandBoyle and Hooke placed the barometer inside the glass vessel of an air pump, precisely measuring the relationship between gas volume and pressure by varying the vessel's air pressure, providing key data for Boyle's law while driving the barometer's transformation from a qualitative demonstration tool into a precision quantitative measuring instrument.