In 1862 the British Asociation for the Advancement of Science wanted to fund a series of flights to study the upper atmosphere. Coxwell (1819-1900) was to pilot the balloon with scientist James Glaisher (1803-1909). On 17 July 1862 they reached an altitude of 26,177 foot on their first ascent without oxygen. On 5 September of that year, using the 'Mars' balloon, they managed to reach a height of over 30,000 foot, breaking the world altitude record in a balloon and becoming the first men to enter the stratosphere.
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