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
Wedgwood scale thermometer to temperatures below 356 °C, which is too low for many industrial applications such as pottery, glass making and metallurgy. To solve this problem, the English potter Josiah Wedgwood proposed, in the 18th century, a method to measure temperatures in his kilns. His method and temperature scale were then widely adopted in science and technical applications. They were abandoned after the invention of accurate types of pyrometer, for example the pyrometer of John Frederic Daniell in 1830. A 0.5-inch-diameter cylinder made from pipe clay was dried at the temperature of boiling water. This would prepare it for heating in