Celsius to variations in barometric pressure. For example, an altitude change of only 28 cm (11 in) causes the boiling point to change by one millikelvin. Celsius The Celsius scale, also known as the centigrade scale, is a temperature scale used by the International System of Units (SI). As an SI derived unit, it is used by all countries except the United States, the Bahamas, Belize, the Cayman Islands and Liberia. It is named after the Swedish astronomer Anders Celsius (1701–1744), who developed a similar temperature scale. The degree Celsius (°C) can refer to a specific temperature on the Celsius scale
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