Jacob Theodor Klein (nickname Plinius Gedanensium; 15 August 1685 – 27 February 1759) was a German jurist, historian, botanist, zoologist, mathematician and diplomat in service of Polish King August II the Strong. Life Klein was born on 15 August 1685 in Königsberg, Duchy of Prussia (now Kaliningrad, Russia). He studied natural history and history at the University of Königsberg. Between 1706 and 1712, Klein travelled through England, Germany, Holland and Austria in an educational journey, before returning to Königsberg. He moved to Danzig after the death of his father, where he was elected city secretary in 1713. Between 1714 and 1716 he served as the city's representative, or “resident secretary at court,” (residierender Sekretär) in Dresden and then Warsaw. Klein began his scientific works in 1713 and began publishing his findings by 1722, as a member of the Institute of Sciences in Bologna. Influenced by Johann Philipp Breyne, his works dealt with matters of zoological nomenclature, and he set up his own system of classification of animals, which was based on the number, shape, and position of the limbs. He used his position as secretary to found a botanical garden there (now called Ogród Botaniczny w Oliwie). For his work in the natural sciences, Klein had been rewarded with membership of several scientific societies, including the Royal Society in London, the Academy of in St. Petersburg, the Deutsche Gesellschaft in Jena, and the Danzig Research Society. One of Klein's daughters, Dorothea Juliane Klein, married physicist Darniel Gralath, who would become mayor of Danzig. Gralath inherited Klein's library, which was praised by Swiss mathematician Jogann Bernoulli. Klein died on 27 February 1759 in Danzig. Botanical garden and "Museum Kleinianum" Using his position as secretary of Danzig and with the help of other scholars, Klein set up a botanical garden in 1718, which was one of, if not the largest of its time. The garden was expanded to include live animals, zoological, fossil and amber collections, the shell collection of the mayor of Amsterdam Nicolaus Witsen, as well as a greenhouse which he used for experimentation with exotic plants. The collection became known as the Museum Kleinianum. It was sold to Margrave Friedrich of Brandenburg-Kulmbach in 1740. After the Margrave's death in 1763, the collection was donated to the Friedrich-Alexander Universität Erlangen-Nürnberg (FAU). It was praised by prominent Swiss mathematician Johann Bernoulli, who visited the museum in 1777 or 1778. Scientific works