Sergey Stepnyak-Kravchinsky (1851–1895) was a Ukrainian revolutionary mainly known for assassinating General Nikolai Mezentsov, the chief of Russia's Special Corps of Gendarmes and the head of the country's secret police, with a dagger in the streets of Saint Petersburg in 1878. After the killing, he exposed himself to danger by remaining in Russia, and he left the country in the fall of 1878. He settled for a short time in Switzerland, then a favourite resort of revolutionary leaders, and after a few years came to London. He was already known in England for Underground Russia, which had been published in London in 1882. The book was followed by a number of other works on the condition of the Russian peasantry, on nihilism, and on the conditions of life in Russia. Russian anarchist leader Peter Kropotkin, who knew Stepnyak personally, testified to his character: "He was a stranger to the feeling of fear; it was as foreign to him as colors are to a person born blind. He was ready to risk his life every moment. Egotism as well as narrow partisanship was unknown to him; he believed that in a movement to defeat oppression there are always parties and factions with differences of opinion. ... He also could not understand why there should be strife among the various parties, since all are involved in the struggle against a common enemy." This photograph of Stepnyak was taken in the 1880s.Photograph credit: Elliott & Fry; restored by Adam Cuerden