Linné on line 
Mathematics in Linnaeus’ time "our honest Klingenstierna" A journey of learning is started
A journey of learning is started
In 1720 Klingenstierna was employed at the Royal 'Kammarkollegium' [now the Swedish Legal, Financial, and Administrative Services Agency] in Stockholm as a clerk. But this did not mean he abandoned mathematics. In his spare time he studied Newton, Leibniz, Huygens, the Bernoulli brothers, l’Hospital, and many others.
Guillaume de l’Hospital's Analyse des Infiniment Petits (published in 1696) is the first textbook on differential calculus.
He was also commissioned to review texts in the newly started scientific journal Acta Literaria Suecia, which was published by Bokwettsgillet (Society of Book Knowledge) in Uppsala. This shows that he already enjoyed a good reputation in scientific circles in Sweden.
Back in Uppsala in 1725 he probably taught the new calculus at Duhre's school of theory and practice.
In 1727 he was awarded the Helmfelt travel scholarship, which gave him an opportunity to undertake an educational tour of the scientific centers of Europe. He first went to Marburg and the tutelage of the philosopher-mathematician Christian Wolff in December 1727. Wolff had written several textbooks in mathematics, logic, and mechanics, and many students from all over Europe traveled to Marburg to learn from him.
Wolff wrote some of the first textbooks on differential calculus. Elementa Matheseos first appeared in 1713.
During his time in Marburg Klingenstierna wrote a dissertation on third-degree curves, elaborating some of Newton's theories from 1704. On the strength of this and a recommendation from Christian Wolff, Klingenstierna was appointed professor of mathematics at Uppsala after Elof Steuch in August 1728. He was allowed to continue his educational tour and now also had a professor's salary.
Stations on Klingenstierna's journey 1727–1730. From the collections of Uppsala University Library.