form of Iphigenia, who has come to question the stranger as to his origin and the purpose of his visit to Tauris.  In broken accents he tells her—­what is new to her ears—­the tale of the murder of Agamemnon, and the vengeance taken upon Clytemnestra by himself; adding, in order to conceal his own identity, that Orestes is also dead, and that Electra is the sole remnant of the house of Atreus.  Iphigenia bursts into a passionate lament, and the act ends with her offering a solemn libation to the shade of her brother.

In the third act Iphigenia resolves to free one of the victims, and to send him with a message to Electra.  A sentiment which she cannot explain bids her choose Orestes, but the latter refuses to save his life at the expense of that of his friend.  A contention arises between the two, which is only decided by Orestes swearing to take his own life if Pylades is sacrificed.  The precious scroll is thereupon entrusted to Pylades, who departs, vowing to return and save his friend.

In the fourth act Iphigenia is a prey to conflicting emotions.  A mysterious sympathy forbids her to slay the prisoner, yet she tries to steel her heart for the performance of her terrible task, and calls upon Diana to aid her.  Orestes is brought on by the priestesses, and while urging Iphigenia to deal the blow, blesses her for the pity which stays her hand.  Just as the knife is about to descend, the dying words of Orestes, ‘Was it thus thou didst perish in Aulis, Iphigenia my sister?’ bring about the inevitable recognition, and the brother and sister rush into each other’s arms.  But Thoas has yet to be reckoned with.  He is furious at the interruption of the sacrifice, and is about to execute summary vengeance upon both Iphigenia and Orestes, when Pylades returns with an army of Greek youths—­whence he obtained them is not explained—­and despatches the tyrant in the nick of time.  The opera ends with the appearance of Pallas Athene, the patroness of Argos, who bids Orestes and his sister return to Greece, carrying with them the image of Diana, too long disgraced by the barbarous rites of the Scythians.

‘Echo et Narcisse,’ an opera cast in a somewhat lighter mould, which was produced in 1779, seems to have failed to please, and ’Iphigenie en Tauride’ may be safely taken as the climax of Gluck’s career.  It is the happiest example of his peculiar power, and shows more convincingly than any of its predecessors where the secret of his greatness really lay.  He was the first composer who treated an opera as an integral whole.  He was inferior to many of his predecessors, notably to Handel, in musical science, and even in power of characterisation.  But while their works were often hardly more than strings of detached scenes from which the airs might often be dissociated without much loss of effect, his operas were constructed upon a principle of dramatic unity which forbade one link to be taken from the chain without injuring the continuity