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The book was widely translated in Darwin's lifetime, but problems arose with translating concepts and metaphors, and some translations were biased by the translator's own agenda. Darwin distributed presentation copies in France and Germany, hoping that suitable applicants would come forward, as translators were expected to make their own arrangements with a local publisher. He welcomed the distinguished elderly naturalist and geologist Heinrich Georg Bronn, but the German translation published in 1860 imposed Bronn's own ideas, adding controversial themes that Darwin had deliberately omitted. Bronn translated "favoured races" as "perfected races", and added essays on issues including the origin of life, as well as a final chapter on religious implications partly inspired by Bronn's adherence to Naturphilosophie. In 1862, Bronn produced a second edition based on the third English edition and Darwin's suggested additions, but then died of a heart attack. Darwin corresponded closely with Julius Victor Carus, who published an improved translation in 1867. Darwin's attempts to find a translator in France fell through, and the translation by Clémence Royer published in 1862 added an introduction praising Darwin's ideas as an alternative to religious revelation and promoting ideas anticipating social Darwinism and eugenics, as well as numerous explanatory notes giving her own answers to doubts that Darwin expressed. Darwin corresponded with Royer about a second edition published in 1866 and a third in 1870, but he had difficulty getting her to remove her notes and was troubled by these editions. He remained unsatisfied until a translation by Edmond Barbier was published in 1876. A Dutch translation by Tiberius Cornelis Winkler was published in 1860. By 1864, additional translations had appeared in Italian and Russian. In Darwin's lifetime, Origin was published in Swedish in 1871, Danish in 1872, Polish in 1873, Hungarian in 1873–1874, Spanish in 1877 and Serbian in 1878. By 1977, it had appeared in an additional 18 languages.

Why was Darwin unhappy with the first French translation of On the Origins of Species?
numerous explanatory notes giving her own answers to doubts that Darwin expressed