In the second act we are left in the dark as to what has happened since we left Isolda in Tristan's arms on the deck of the ship. Some years ago an excited discussion took place on a very momentous question--"Did Isolda marry King Mark or not?" If not, it was strange that she should have been left free enough apparently to see Tristan whenever she wished, and Mark's expostulations at the end of the act seem rather unwarranted in the mouth of a man whose honour, in the Divorce Court sense, has not been smirched; yet, on the other hand, it is unlikely that a legendary King, with the bride in his palace, would wait so long for the marriage as to allow the many pretty incidents mentioned by Brangaena to happen. Yet again, if they were married, Mark, in the third act, shows a more than heroic willingness and less than cuckold readiness to let Isolda go free. Probably Wagner never gave the problem a moment's consideration, which is hardly surprising when we consider his own multitudinous love affairs. He was not writing a Sunday-school tract, but a drama of passion so intense that purity, prudence and all such considerations were thrown to the winds. The act opens with a very Proteus of a theme. Its entrance is like a thunder-clap in a cloudless sky. The conductor lifts his stick, and then-- [Illustration: Some bars of music] --an unprepared discord which must have pained the ears and grieved the hearts of the ordinary opera-goers and pedants when the opera was first given. This subject is used in connection with the notion of daylight as a nuisance to lovers in the subsequent conversation of Tristan and Isolda--a notion which we shall examine presently. Presently another subject is heard, one of which extensive use is made in the first scene-- [Illustration: Some bars of music] The curtain rises. It is a sultry summer night; the black woods stand round a garden; on the left is the castle of Mark, with a torch blazing at the doorway, making the surrounding night blacker. Sounds of hunting-horns are dying away in the distance. Brangaena and Isolda are there listening, and Brangaena, to music of enchanting beauty, is warning Isolda that the hunters can be no great way off. "Listen to the brook," says Isolda. "How could I hear that if the horns were near?" Then comes one of Wagner's matchless bits of painting--the brook rippling through the silent night. Isolda is now going to extinguish the torch, as a signal to Tristan that he may approach. Brangaena protests, and warns Isolda against Melot, who has arranged this night hunt as a trap to catch Tristan; and she bewails the officiousness which led her to substitute the love-philtre for the poison. The rest of the scene may be passed over. The music is woven out of themes just quoted, and another which will play a big part in the love-duet: [Illustration: Some bars of music]