An early reference to the concept is found in the betting book for Brooks's, a London gentlemen's club. The 1785 entry (only two years after the first successful balloon ascent by Étienne Montgolfier) reads: "Ld. Cholmondeley has given two guineas to Ld. Derby, to receive 500 Gs whenever his lordship sex with a woman in a balloon one thousand yards from the Earth." (However, there is no further indication that the bet was paid, or even how they would check it if it was claimed.)