John Jeffries (1796-1876) was an ophthalmic surgeon and co-founded the Massachusetts Charitable Eye and Ear Infirmary. John Jeffries John Jeffries (5 February 1745 – 16 September 1819) was a Boston physician, scientist, and a military surgeon with the British Army in Nova Scotia and New York during the American Revolution. He is best known for accompanying Jean-Pierre Blanchard on his 1785 balloon flight across the English Channel. Born in Boston, Jeffries graduated from Harvard College and obtained his medical degree at the University of Aberdeen. Dr. Jeffries played a large role in the trial for the Boston Massacre as a witness for
Hot air balloon are unaware that is possible to sail through the element air"). Persecuted by the Inquisition, he was prevented from continuing his research; however, he left designs for a manned air vessel. The French brothers Joseph-Michel and Jacques-Étienne Montgolfier developed a hot air balloon in Annonay, Ardeche, France and demonstrated it publicly on September 19, 1783, making an unmanned flight lasting 10 minutes. After experimenting with unmanned balloons and flights with animals, the first balloon flight with humans aboard, a tethered flight, performed on or around October 15, 1783, by Jean-Francois Pilatre de Rozier who made at least one tethered flight