an American physician and politician. He was brother of John Jay, one of the Founding Fathers of the United States. While initially a supporter of American independence, he later changed his views becoming a Loyalist and went into exile in London after the Treaty of...

an American physician and politician. He was brother of John Jay, one of the Founding Fathers of the United States. While initially a supporter of American independence, he later changed his views becoming a Loyalist and went into exile in London after the Treaty of Paris recognised independence. Invisible ink was used occasionally after Sir James Jay invented two special fluids, and sent a supply to his brother John Jay in New York. Sir James would use the ink at the bottom of brief, friendly letters to his brother and even send the letters unsealed, so that British authorities might inspect the contents.

a Boston physician, scientist, and a military surgeon with the British Army in Nova Scotia and New York during the American Revolution. Born in Boston, Jeffries graduated from Harvard College and obtained his medical degree at the University of Aberdeen. He is best known for accompanying Jean-Pierre Blanchard on his 1785 balloon flight across the English Cha...

a Boston physician, scientist, and a military surgeon with the British Army in Nova Scotia and New York during the American Revolution. Born in Boston, Jeffries graduated from Harvard College and obtained his medical degree at the University of Aberdeen. He is best known for accompanying Jean-Pierre Blanchard on his 1785 balloon flight across the English Channel. Dr. Jeffries also played a large role in the trial for the Boston Massacre as a witness for the defense.

an English physician and scientist who was the pioneer of smallpox vaccine, the world's first vaccine. The terms "vaccine" and "vaccination" are derived from Variolae vaccinae (smallpox of the cow), the term devised by Jenner to denote cowpox. He used it in 1798 in the long title of his Inquiry into the...Variolae vaccinae...known...[as]...the Cow Pox...

an English physician and scientist who was the pioneer of smallpox vaccine, the world's first vaccine. The terms "vaccine" and "vaccination" are derived from Variolae vaccinae (smallpox of the cow), the term devised by Jenner to denote cowpox. He used it in 1798 in the long title of his Inquiry into the...Variolae vaccinae...known...[as]...the Cow Pox, in which he described the protective effect of cowpox against smallpox.