John Jeffries a letter he dropped from the balloon during his historic flight, considered the oldest piece of airmail in existence. He fled to Halifax, Nova Scotia in 1776 and later to England 1779, and was employed by the Crown during this time. In 1785, Jeffries and Jean-Pierre Blanchard crossed the English Channel in a balloon, becoming the first human beings to cross the Channel by air. Jeffries lived in England from 1779 to 1790. Despite being named in the Massachusetts Banishment Act, he returned to private practice in Boston, staying there until his death in 1819. His son John Jeffries II
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