By the early nineteenth century, meteorologists were equipped with plenty of useful devices: barometers, thermometers, hygrometers, and any number of variations thereon. But the nature of these instruments was not wholly understood. While it was possible to take accurate measurements with a barometer, what physical process made the mercury move? What exactly is atmospheric pressure? And how can one measure sunlight? Ranging from wild theories of gravity-resistant air particles to the latest experiments in altitude, chemist and physicist John Frederic Daniell (1790 1845) presents his answers...
By the early nineteenth century, meteorologists were equipped with plenty of useful devices: barometers, thermometers, hygrometers, and any number of ...