I thought that it was interesting for people interested in Greek and Latin composition (and reading in general):
I have looked for the German in the translator's stated sources, but have been unable to find it so far. Niebuhr's letters are thoughtful and very attractive. I will have to read more of them.For the study of language, I recommend to you especially Demosthenes and Cicero. Select, in the former, the Oration "pro Corona;" in the latter, the "pro Cluentio," and read them with all the thoughtfulness of which you are capable: then go through them so that you could give account of every word and every phrase; draw a sketch of their argument; try to get a clear idea of all the historical circumstances, and to bring them into order. This will give you an immense amount of labor, and from it you will learn how little we can know, and, consequently, you do know. Apply then to your tutor, not in order to surprise him with unexpectedly difficult problems; for there are--in the Cluentiana, for instance--difficulties with regard to facts which the profoundest student can only solve by hypotheses which do not present themselves immediately to any scholar; but that he may be so kind as to consult and think over the passages on which you have exhausted your powers and resources. In the Cluentiana, develop the system of indictment. Make collections of words and expressions, especially epithets with their substantives, and the original sense of the figurative expressions. Translate; after a few weeks turn your translation back again into the original language.
Besides this grammatical work, read those great authors one after the other with greater freedom; but after having finished a book or a section, recall what you have read by an act of memory, and indicate the contests with the greatest brevity. Then besides, write down expressions and phrases that particularly occur to you; so too you ought to write down every new word immediately, and read over the list at night.