One of the most important rhythmic means of intensifying expression is, of course, the rubato. The late romantic musician considered this device the heart of expressiveness in tempo. In the early nineteenth century burgeoning Romanticism first induced musicians in general to extract expression from the free kind of tempo modification that affects the entire musical fabric. To restrict performers from taking excessive liberties in the lied, composers resorted more and more to measured tempo modifications. All late romantics, especially the impressionists among them, struggled to "liberate" music from its rhythmic bondage, to achieve a kind of liquid rhythmic flow, unhampered by any regularity of pulsation — a tempo dominated by expression. Joseph Marx, who often sought such freedom, such "flowing movement," achieved this result in Nocturne, not only through its multiple time signatures and its performance direction, but mainly through the kind of rhythmic configurations he assigned the pianist.