loved him and he has loved her. He has killed her betrothed, Morold, and
she conceives it to be her duty to kill him, but she cannot. Tristan
dare not aspire to win her, and when she is claimed by his uncle, King
Mark of Cornwall, he is sent to bring her. At this point the opera
opens.

The prelude begins with one of the love themes; other themes are worked
in; the parts weave and interweave with each other, swelling and
mounting until a shattering climax is reached; then all subsides, and an
effect of terrible suspense is produced by the last subdued phrase in
the bass as the curtain rises, and we feel that something tragic is to
come. Here we have Wagner the full and ripe musician. As a technical
achievement this prelude is marvellous; the polyphony is as intricate
and yet as sure as anything in Bach or Mozart, part winding round part,
and each going its way steadily to the climax; and the white-hot passion
expressed by this means makes the thing a miracle. There is nothing like
it in _Tannhäuser_ and _Lohengrin_. Here we are entirely free of the
Weberesque four-bar phrases; the rhythms are subtle and complex, though
to the ear they sound clear and simple enough. When the curtain goes up
we see a sort of tent arranged on the deck of a ship. From aloft a
sailor chants a wild sea-song, unlike any sea-song ever chanted off the
stage and yet redolent of the sea and salt winds.

[Illustration: Some bars of music]

Isolda is lying on a couch, her face buried in her hands; Brangaena
stands by. In the sailor's song she has fancied some gibe at herself,
for she is being carried off against her will by the man she loves to
wed an old man she has never seen. She starts up in rage, and then,
realizing her position, asks Brangaena where they are. Now, Wagner, if