Medical thermometer Bahamas, Belize, and the Cayman Islands. Prominent Dutch mathematician, astronomer and physicist Christiaan Huygens created a clinical thermometer in 1665, to which he added an early form of the centigrade scale by setting the scale to the freezing and boiling points of water. By 1742 Swedish astronomer Anders Celsius created the Celsius temperature scale that was the reverse of the modern scale, in that "0" was the boiling point of water, while "100" was freezing. It would later be reversed by Swedish botanist Carolus Linnaeus (1707–1778) in 1744. Working independently of Celsius, the Lyonnais physicist Jean-Pierre Christin, permanent secretary of
John Jones (astronomer) John Jones (astronomer) John Jones (18181898), also known as Ioan Bryngwyn Bach and Y Seryddwr ("The Astronomer"), was a Welsh amateur astronomer. He was born at Bryngwyn Bach, Dwyran, Anglesey, and received only an elementary education. From the age of twelve, he worked as a farm labourer. He later worked as a counter of cargoes of slate as they were loaded on to ships in Bangor, in modern Gwynedd. Unusually for someone of his background, he was not only a musician and a poet but proficient in several languages. He is noted mainly for his interest in astronomy: he constructed