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
Temperature zero point, , is defined to coincide with the coldest physically-possible temperature (called absolute zero). Its degrees are defined through thermodynamics. The temperature of absolute zero occurs at = (or ), and the freezing point of water at sea-level atmospheric pressure occurs at = . The International System of Units (SI) defines a scale and unit for the kelvin or thermodynamic temperature by using the reliably reproducible temperature of the triple point of water as a second reference point (the first reference point being at absolute zero). The triple point is a singular state with its own unique and invariant