fourth ballast-flow periods, this rise in "ceiling" is attributed to the cooling of the air entrapped in the aneroid of the automatic ballast valve. This decrease of pressure of 21 mb corresponds to a loss of 8°C of superheat. In each of the four periods of ballast flow, there was enough unnecessary ballast lost to cause an overshoot when the balloon returned to its floating level. This excess ballast was that used during the period when the balloon had begun to rise but was still below activation altitude of the automatic ballast valve. The inefficient use of ballast was one of the major objections to such a control system.
On this flight the ballast load of 3 kilograms was exhausted in only three hours, indicating a large loss of gas from this particular balloon. It is believed that the large initial acceleration provided by the rapid descent of the balloon caused the restoring force, and the subsequent overshoot, to be very large, and the high ballast flow is probably much greater than was the loss of buoyancy on this flight.
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