The Greeks, as every scholar knows, took great latitude with _time_ in their representations. The interval between one act and another, often even the time occupied by the chaunting of the chorus, frequently was made to cover a very considerable period, during which battles were fought, a duel or a conspiracy broke forth, an execution took place, and the most momentous events of the piece off the stage occurred. In place, it is true, they were strictly limited; the scene never changed, and all the incidents were introduced by bringing successive persons upon it. In this respect, it may be admitted, they carried their strictness too far. Probably it arose from the pieces being represented, for the most part, in the open air, under circumstances when the illusion produced by a change of scene, such as we witness at our theatres, was difficult, if not impossible, from the audience being, for the most part, above the actors, and the stage having no top. But to whatever cause it may have been owing, we hold the adherence to unity of place an unnecessary and prejudicial strictness in the Greek theatre. But a very slight deviation from it alone seems admissible; and the unity of action or emotion seems to be the very essence of this species of composition. The true principle appears to be, that the place should not change to a greater extent than the spectators _can conceive the actors to have gone over without inconvenience within the time embraced in the representation_. This time often extended with the Greeks to a half of, or even a whole day, and there seems nothing adverse to principle in such extension. Changes of scene, therefore, from one room in a palace to another; from one part of a town to another; or even from town to a chateau, garden, forest, or other place in its near vicinity, appear to be perfectly admissible, without any violation of true dramatic principle. The popular opera of the "Black Domino," to which the charming singing and acting of Madame Thillon have recently given such celebrity at the Haymarket, may be considered in this respect as a model of the unities taken in a reasonable sense. The time which elapses in the piece is a single night; the subject is the adventures which befel the heroine during that period; the scene changes, but only to the places in the same town to which she went during its continuance. There seems nothing inconsistent with the production of unity of interest in such a latitude. And with this inconsiderable expansion of the old Greek unities, it will be found that Shakspeare's greatest plays, and those which experience has found to be best adapted for the stage, have been constructed on the true principles.