Within these limits Lysias aimed at elasticity; though the form of the speech was to be settled precisely, his artistic sense demanded a variety in the details. It is remarked by Dionysius that, though he composed two hundred speeches, he never used the same preface twice. Some orators were in the habit of using over again the opening sentences which had already served as introduction to an old speech, and even borrowing such _proems_ whole from the speeches of their predecessors or from rhetorical handbooks. Lysias, with a truer instinct for what was appropriate, composed for every speech a _proem_ adapted to its requirements. His versatility in this small matter is much to be admired. It is to be noticed also that there is considerable variety in his ways of ending his speeches; though many of his epilogues practically say the same thing in different words, they nearly all succeed in saying it in a way more appropriate to the particular speech than to any other. As there is diversity in these forms, so there is great variety in the details of expression. There are very few formal mannerisms on which we could seize if we wished to produce a parody of the style. There are indeed one or two common necessary phrases which he employed frequently, but even these are presented in different shape from time to time.[121] § 4 Lysias varies greatly in the structure of his sentences, at one time producing periods neatly turned, with clauses carefully balanced, at another time writing in a style by no means periodic; again varying his form by mingling the two methods, inserting in the middle of the period a parenthesis or relative clause which keeps us in suspense, or attaching to the end of the period an extra limb which, from a technical point of view, spoils its symmetry. It is impossible without quoting a large number of examples to prove these statements in detail, but we may state broadly that in speeches dealing with serious matters of public interest the style is more periodic; in some of the private speeches on comparatively trivial subjects the style is simpler and more straightforward.