The opening of Author'S Preface
When I left Constantinople for Odessa my principal object was to investigate the geology of the Crimea and of New Russia, and to arrive by positive observations at the solution of the great question of the rupture of the Bosphorus. Having once entered on this pursuit, I was soon led beyond the limits of the plan I had marked out for myself, and found it incumbent on me to examine all the vast regions that extend between the Danube and the Caspian Sea to the foot of the northern slope of the Caucasus. I spent, therefore, nearly five years in Southern Russia, traversing the country in all directions, exploring the course of rivers and streams on foot or on horseback, and visiting all the Russian coasts of the Black Sea, the Sea of Azof and the Caspian. Twice I was intrusted by the Russian government with important scientific and industrial missions; I enjoyed special protection and assistance during all my travels, and I am happy to be able to testify in this place my gratitude to Count Voronzof, and to all those who so amply seconded me in my laborious investigations.