COMPACT, conventional, rigid in appearance, the sonnet has been, for six centuries, a miraculous wine-press through which the richest, the quintessential elements of the human spirit have been strained. It is the unique mode for achieving brevity, beauty and power together-like a kind of wing, suited to short but splendid flight. It seems to be a natural pattern, corresponding to some fundamental process of the mind, "when emotion is either too deeply charged with thought, or too much adulterated with fancy, to pass spontaneously into the movements of the lyric." It flourishes in the greatest periods of poetry and makes a special appeal to nearly all great poets.
The original rules of the sonnet were extremely strict, but they have been varied or violated so often and so successfully in English that now some four or five forms can be recognized. At least, a sonnet should be confined to a single thought, feeling, or mood; and to fourteen decasyllabic lines, following a definite rhyme scheme. Yet the "caudated" or "mock sonnets" of Meredith's Modern Love are in sixteen lines.
In the present period of literary anarchy, of æsthetic radicalism, the sonnet has more than held its own in the fine achievements of such different poets as John Masefield, Edwin Arlington Robinson, Rupert Brooke, Edna St. Vincent Millay, Edgar Lee Masters, George Sterling, Arthur Davison Ficke, W. W. Gibson, and Elinor Wylie. Fiery leaders in the free verse movement of ten years ago are now turning to the traditional quatorzain. And David Morton even shows that in the twentieth century new values are being given to the sonnet in the way of informality, intimacy, character portraiture, and singing lyricism.