He frequently traveled to his family's estate on the Crimean coast from St. Petersburg and to and from Simferopol, in the interior of the peninsula. The floral and geographical diversity of the Crimean peninsula, as well as the starker geographical transitions between the capital and his home, did much to awaken an interest in the relationship between climate and the natural world. In 1867, he transferred to the University of Heidelberg and in 1870 he defended his doctorate dissertation on the effects of temperature on plant growth at the University of Leipzig. He served in the Prussian ambulance corps in the Franco-Prussian War and later worked at the Central Physical Observatory in St. Petersburg.