Letters of Alexander Von Humboldt

Written Between the Years 1827 and 1858, to Varnhagen Von Ense; Together with Extracts from Varnhagen's Diaries, and Letters from Varnhagen and Others to Humbol... » 

Written Between the Years 1827 and 1858, to Varnhagen Von Ense; Together with Extracts from Varnhagen's Diaries, and Letters from Varnhagen and Others to Humboldt «