Carl Friedrich Gauß and Christopher Hansteen. The correspondence between the two scholars in its historical context (Q2260303)

This is another work of the successful researcher/writer team on Carl Friedrich Gauß. While their monumental work on the correspondence of Gauß with Russian scientists [Carl Friedrich Gauß und Russland. Sein Briefwechsel mit in Russland wirkenden Wissenschaftlern. Berlin: De Gruyter (2012; Zbl 1235.01033)] revealed the intense connections of Gauß\ with a large number of scientists the present study gives the correspondence of Gauß with the Danish mathematician and astronomer Christopher Hansteen. Both men were eager to understand the Earth's magnetism and this topic is at the centre of their correspondence. Hansteen was born in 1784 in Christiania (today Oslo) and therefore seven years Gauß's junior. Educated at the University of Kopenhagen and taught by Hans Christian Oerstedt he started as a mathematics teacher in Frederiksborg, won the award of the Royal Danish Society of Sciences on a question of magnetism and was called to lecture mathematics at the University of Christiania in 1814. Two years later, he became professor of astronomy and applied mathematics as well as the director of the lately erected interim observatory in Christiania. He not only did theoretical work concerning the magnetism of the Earth but also led measurement expeditions as far as into Russia (1828--1830). The correspondence with Gauß started in 1833. Hansteen in fact designed and built instruments to measure the magnetic field of the Earth and Gauß used at least one of his instruments; Hansteen even visited Gauß in Göttingen in the summer of 1839. Becoming a member of a number of scientific societies he continued to undertake several expeditions to measure the magnetic field of the Earth as well as measuring the length of meridians. Hansteen died in 1873, 18 years after the death of Gauß. The present book is based on thorough research and is remarkably edited. The authors describe their criteria of their editorial work in detail. The transliteration of cyrillic names is done following the ISO standard. Following an introduction to which time tables of the lives and works of Hansteen and Gauß are given the second chapter contains detailed information concerning the career and work of Hansteen. The third chapter is devoted to the relationship of Hansteen with Gauß, followed by some remarks on the relationship between Hansteen and Alexander von Humboldt in the fourth chapter. Chapter five contains the correspondence between Gauß and Hansteen of which Chapter six gives a register of the letters. Five appendices give additional information like a chronology of Hansteen's journey through Russia or seven tables showing maps from Hansteen's ``Magnetischer Atlas'' (1819). This book not only gives deep insights into Gauß's and Hansteen's research concerning the Earth's magnetic field but also into their private lives. It will add to our understanding of how the research on the magnetism of our planet went on in the 19th century which shaped our understanding of it today. The work is excellently researched and edited and the publisher did a great job to produce a beautiful book. The language used is exclusively German.