Physics and a pressurized cabin
Educated in engineering and science in Zurich, Piccard became a physics professor at the Université libre de Bruxelles in 1922. His enclosed balloon gondola maintained internal pressure, allowing researchers and instruments to enter the thin upper atmosphere.
The 1931 flight
On 27 May 1931 Piccard and Paul Kipfer ascended from Augsburg to 15,781 metres. From the pressurized cabin they collected information about the upper atmosphere and cosmic rays while testing the gondola and the balloon’s suitability for scientific investigation.
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From balloon to bathyscaphe
Piccard’s bathyscaphe combined a pressure-resistant sphere with a float containing low-density liquid. Ballast controlled descent and could be released for ascent, rather than relying on a suspension cable. An early craft made an unmanned trial dive in 1948. Piccard dived with his son Jacques in Trieste in 1953; Jacques and Don Walsh, rather than Auguste, made the 1960 Challenger Deep descent.