It is not the intention of this article to enter into the question of what constitutes the interest of such plays as "Rip Van Winkle." To do so would be to enter into a field where everything is uncertain, and where judgment is only an expression of individual liking. The main elements of the success appear to be humor and pathos, those twin brethren of genius whose identity and individuality are frequently so inextricable from each other. Both are drawn in broad, simple lights and shadows, so that the simplest audience can take the points, while the most cultivated members of that audience are studying the delicate touches of the actor. The contrast between--but we must refrain from the digression, however tempting. We are examining the dramatic canons, and the only settled canons about which there is little doubt are those relating to construction, not to sources of interest. In the kingdom of invention genius is supreme, and amenable to no rules. Each writer must work out his own salvation. Constructively it is obvious that the number of acts in a play must be regulated by the number of natural episodes in the action of its subject; and the perfection of its construction is tested by the liberties that can be taken with the acts and scenes. Of late years it has become the fashion to alter and remodel Shakespeare's and other old plays, by changing scenes and acts, cutting out and putting in. To an ardent worshipper of Shakespeare as read, these alterations frequently appear desecrations, but there is little question that they were and are improvements. The construction of many of Shakespeare's plays is decidedly faulty, and the nature of the improvements made by managers and actors is best illustrated when the original play unaltered is tried against the adaptation. The acting edition of "Richard III." is a familiar instance of this. Colley Cibber arranged it, he being a shrewd old actor and manager. His edition holds the stage today, and always succeeds, where the original "Richard" fails. In this matter of construction the chances are all in favor of the improvement of a work by a shrewd adapter. His attention is directed to only one thing, the successful presentation of the play. He is not an artist so much as a workman. He creates nothing, he only alters and improves. He may be perfectly incapable of creating an ideal character, while yet he can make its language more compact, can concentrate its action. Such an adapter is a skilful gardener. He cannot create the fruit tree, but he can prune it, and stimulate it to the perfection of fruit-bearing.