John Jefferies (1744-1819),US physician,meteorologist and balloon aviation pioneer. Jefferies was a British military surgeon during the American Revolution. In London,in 1784,he made a scientific study of the air at high levels. He approached French balloonist Jean-Pierre Blanchard and (with a barometer,thermometer,hygrometer,electrometer,and mariner's compass) they made two flights: London to Dartford,and the 1785 first aerial crossing of the English Channel. Artwork from 'Aerostation - Aviation' (1911) by French civil engineer Max de Nansouty (1854-1913),part of the 'Les merveilles de la science' series of 1867-1891 by Louis Figuier |