Anders Celsius independent of latitude (and of atmospheric pressure). He determined the dependence of the boiling of water with atmospheric pressure which was accurate even by modern-day standards. He further gave a rule for the determination of the boiling point if the barometric pressure deviates from a certain standard pressure. He proposed the Celsius temperature scale in a paper to the Royal Society of Sciences in Uppsala, the oldest Swedish scientific society, founded in 1710. His thermometer was calibrated with a value of 100° for the freezing point of water and 0° for the boiling point. In 1745, a year after Celsius'
Stephen Alexander (astronomer) Stephen Alexander (astronomer) Stephen Alexander (September 1, 1806 – June 25, 1883) was a noted astronomer and educator. He was born in Schenectady, New York. He was the brother-in-law of Joseph Henry, the first secretary of the Smithsonian, and worked closely with him. He graduated from Union College in 1824. He became a tutor in mathematics at Princeton University in 1832; he would later become professor of astronomy and mathematics and advocate for the construction of Princeton's first observatory. Alexander relied on the assistance of a free African American man named Alfred Scudder, who worked for him at Princeton during