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 envelope is distended by great pressure depends on its valves not to burst. With one of its valves stopped with wax the "Pax" was allowed to shoot up from the earth, and immediately its occupants seem to have lost their heads. Instead of checking their rapid rise one of them threw out ballast—a handful of which will send up a great spherical balloon perceptibly. The mechanician of Severo is said to have been last seen throwing out a whole bag in his excitement. Up shot the "Pax" higher and higher, and the expansion, the explosion, and the awful fall came as a chain of consequences. The tonnage of my new balloon was 630 cubic metres (22,239 cubic feet), affording an absolute lifting power of 690 kilogrammes (1518 lbs.), but the increased weight of the new motor and machinery, nevertheless, put my disposable ballast at 110 kilogrammes (242 lbs.). It was a four-cylinder motor of 12 horse-power, cooled automatically by the circulation of water round the top of the piston (culasse). While the water cooler brought extra weight, I was glad to have it, for the arrangement would permit me to utilise, without fear of overheating or jamming en route, the full power of the motor, which was able to