John Jeffries (Jeffries John)

(1744-1819)
Born February 5, 1744 in Boston (pc. Mass.). In 1763 he graduated from Harvard University, perfected in medicine in Boston and abroad in 1769 and received his degree from the University of Aberdeen (Scotland). Prior to 1771 practiced as a doctor in Boston, then served in the British military courts and in military hospitals. Participated in the War of Independence on the U.S. side of Britain. After the war he worked as a doctor in England, at the same time interested in the possibility of studying the properties of the atmosphere and winds at different altitudes with balloons. He made two flights in a balloon with P. Blanchard: first, a short, 30 November 1784 from London (the maximum altitude was 2,837 meters), the second - the famous, the world's first flight across the English Channel on Jan. 7, 1785 (from Dover to Calais). Jeffries gave balls instrumentation, which included a thermometer, barometer, electrometer, hygrometer. Air samples taken at different altitudes in the first flight, studied English scientist Dzh.Kavendish. In 1790 Jeffries returned to Boston, where he studied medical practice. Jeffries died in Boston on Sept. 16, 1819.