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
Rozière balloon Rozière balloon A Rozière balloon (or simply Rozière) is a type of hybrid balloon that has separate chambers for a non-heated lifting gas (such as hydrogen or helium) as well as for a heated lifting gas (as used in a hot air balloon or Montgolfière). The design was created by Jean-François Pilâtre de Rozier (1754–1785). A Rozière-type balloon has the advantage of partial control of buoyancy with much less use of fuel than a typical hot air balloon. This reduction of fuel consumption has allowed Rozière balloons and their crew to achieve very long flight times, as much as several