In 1744, the year Anders Celsius died, the famous Swedish botanist Carolus Linnaeus (1707–1778) used a reversed version of Celsius's scale when he bought his first thermometer. This had a scale where zero represented the melting point of ice and 100 represented water's boiling point, similar to what we use it today. His custom-made "Linnaeus thermometer", to use in his greenhouses, was made by Daniel Ekström, then Sweden's leading maker of scientific instruments. Ekstöm's workshop was in the basement of the Stockholm observatory. As often happened in this age before modern communications, many physicists, scientists, and instrument makers are given credit with independently making the same measurement scale; among them were Pehr Elvius, the secretary of the Royal Swedish Academy of Sciences (which had an instrument workshop), who Linnaeus had also talked to; Christin of Lyons; Daniel Ekström, the instrument maker; and Mårten Strömer (1707–1770) who had studied astronomy under Anders Celsius.