Carl Linnaeus stayed on Gotland for about a month, and then returned to Uppsala. During this expedition, they found 100 previously unrecorded plants. The observations from the expedition were later published in ', written in Swedish. Like ', it contained both zoological and botanical observations, as well as observations concerning the culture in Öland and Gotland. During the summer of 1745, Linnaeus published two more books: ' and '. ' was a strictly botanical book, while ' was zoological. Anders Celsius had created the temperature scale named after him in 1742. Celsius' scale was inverted compared to today, the boiling point at
Negative temperature Negative temperature In quantum thermodynamics, certain systems can achieve negative temperature; that is, their temperature can be expressed as a negative quantity on the Kelvin or Rankine scales. A system with a truly negative temperature on the Kelvin scale is "hotter" than any system with a positive temperature. If a negative-temperature system and a positive-temperature system come in contact, heat will flow from the negative- to the positive-temperature system. A standard example of such a system is population inversion in laser physics. Temperature is loosely interpreted as the average kinetic energy of the system's particles. The existence of negative temperature,