The "String Quartet" is constructed upon the form of a theme and seven variations. It is the principal purpose of the theme to provide a unifying musical idea, and the variations to provide a continuous line of development of that idea The characteristics of simplicity and directness in the construction of the theme, not unusual in the variation form, furnish the source materials for extensive development that progresses in levels of complexity in each variation. A return to the theme, again with simplicity and directness, completes the unifying musical idea of the composition.