language is ambiguous, and probably he intended his meaning to be the same.  Isolda has no two opinions about his conduct.  It had been her duty to kill him in the first place, and her love, her destiny, Frau Minna—­call it what you will—­betrayed her; and now she is betrayed by the man whose life she saved.  Had she spoken one word in her father’s castle Tristan would not have returned to Cornwall:  in all likelihood his head would have been sent as an acknowledgment of Morold’s.  Her fury knows no bounds; her grief and sense of ignominious humiliation almost defy expression; her contempt for Tristan, when she finds words for it, is scathing.  All this we learn as the opera proceeds; but we should know the facts of the history before seeing the work the first time, else the first act is bewildering, for matters have arrived just at this point when the curtain rises.

II

The prelude is the only operatic prelude in the world which is an integral, organic part of the drama; it cannot be omitted without detriment to the drama.  In several of Mozart’s operas the overture, by means of a modulation, is made to lead without a break into the first scene; Gluck had done precisely the same thing; Wagner, in the Mastersingers of Nuremberg, did the same thing.  But in the cases of Gluck and Mozart and of Wagner in the Mastersingers, if by chance the parts of the overture were missing, the opera could start away and go on merrily, and we should miss nothing but the preliminary pleasure of hearing the overture.  In the case of Tristan, where Wagner’s art of combining the music and drama in an indivisible whole was at its culminating point—­a point from which it gradually receded—­this is not conceivable.  If the band parts of the Tristan prelude were mislaid it would be well to omit the first act altogether.  What Wagner tried to do in the Flying Dutchman—­to make the whole opera a solid thing from which not one bar might be subtracted without ruining the whole effect—­he achieved once, and once only, in Tristan.

What may seem an irrelevancy turns on this very point.  There is no necessity for reasoning about a work of art; yet there is both pleasure and mental profit in doing so in certain instances.  If there is any necessity at all for understanding Wagner’s mind and Wagner’s art, we may as well do it as thoroughly as we can.  Therefore the reader will perhaps bear with me patiently if I point out something he has doubtless discovered for himself, namely, that Tristan is Wagner’s only opera in which music and drama had birth simultaneously in his brain.  He himself, in several significant passages in his prose writings, indicated this.  He said that when, after several years devoted to expounding his theories in essays,—­mainly, he said, to make these theories clear to himself:  mainly, I think, for the accruing cash—­he began Tristan, he immediately found he had left