Pictet was a travelling-companion, and student, of Saussure, later succeeding him in his university chair. Jefferson, Humboldt (also a friend), Ampère, Ørsted, Berzelius, Berthollet, Chladni, Fourcroy, Lalande, Volta and Zach were among his extensive correspondents. He took Owen on a trip to France and Switzerland (picking up Pictet’s friend Cuvier en route), so Owen could meet with influential continental thinkers. Davy, visiting Geneva with his assistant Faraday, investigated solar radiation with Pictet. De la Rive was one of his colleagues on a significant scientific journal of the time, ‘Bibliothèque Britannique.’ Bonnet complemented him on his mode of interrogation of nature.