Gasparo Berti

Gasparo Berti (about 1600 to 1643) was an Italian mathematician, astronomer and physicist, probably born in Mantua and active mostly in Rome. He is remembered for an experiment in which he unknowingly built the first working barometer. After Galileo's Two New Sciences reached Rome in December 1638, Berti and Raffaello Magiotti tested whether a vacuum could be produced. Berti filled an eleven metre lead tube with water, sealed it, and opened the lower end in a basin; the water settled about ten metres above the basin, the same height seen in Baliani's siphon, leaving an empty space above it that he claimed was a vacuum. The claim was contested, but the experiment led Evangelista Torricelli to study the weight of air and invent the barometer. Berti held a chair of mathematics at La Sapienza and mapped the Roman catacombs, though little of his writing survives.