Harry Potter 06 - Harry Potter and the Half-Blood Prince

said Dumbledore, as he reached the boulder closest to the cliff face. A thousand flecks of golden light sparkled upon the dark surface of the water a few feet below where he crouched; the black wall of rock beside him was illuminated too.
    ‘You see?’ said Dumbledore quietly, holding his wand a little higher. Harry saw a fissure in the cliff into which dark water was swirling.
    ‘You will not object to getting a little wet?’
    ‘No,’ said Harry.
    ‘Then take off your Invisibility Cloak – there is no need for it now – and let us take the plunge.’
    And with the sudden agility of a much younger man, Dumbledore slid from the boulder, landed in the sea and began to swim, with a perfect breaststroke, towards the dark slit in the rock face, his lit wand held in his teeth. Harry pulled off his Cloak, stuffed it into his pocket and followed.
    The water was icy; Harry’s waterlogged clothes billowed around him and weighed him down. Taking deep breaths that filled his nostrils with the tang of salt and seaweed, he struck out for the shimmering, shrinking light now moving deeper into the cliff.
    The fissure soon opened into a dark tunnel that Harry could tell would be filled with water at high tide. The slimy walls were barely three feet apart and glimmered like wet tar in the passing light of Dumbledore’s wand. A little way in, the passageway curved to the left and Harry saw that it extended far into the cliff. He continued to swim in Dumbledore’s wake, the tips of his benumbed fingers brushing the rough, wet rock.
    Then he saw Dumbledore rising out of the water ahead, his silver hair and dark robes gleaming. When Harry reached the spot he found steps that led into a large cave. He clambered up them, water streaming from his soaking clothes, and emerged, shivering uncontrollably, into the still and freezing air.
    Dumbledore was standing in the middle of the cave, his wand held high as he turned slowly on the spot, examining the walls and ceiling.
    ‘Yes, this is the place,’ said Dumbledore.
    ‘How can you tell?’ Harry spoke in a whisper.
    ‘It has known magic,’ said Dumbledore simply.
    Harry could not tell whether the shivers he was experiencing were due to his spine-deep coldness or to the same awareness of enchantments. He watched as Dumbledore continued to revolve on the spot, evidently concentrating on things Harry could not see.
    ‘This is merely the ante-chamber, the entrance hall,’ said Dumbledore after a moment or two. ‘We need to penetrate the inner place … now it is Lord Voldemort’s obstacles that stand in our way, rather than those nature made …’
    Dumbledore approached the wall of the cave and caressed it with his blackened fingertips, murmuring words in a strange tongue that Harry did not understand. Twice Dumbledore walked right around the cave, touching as much of the rough rock as he could, occasionally pausing, running his fingers backwards and forwards over a particular spot, until finally he stopped, his hand pressed flat against the wall.
    ‘Here,’ he said. ‘We go on through here. The entrance is concealed.’
    Harry did not ask how Dumbledore knew. He had never seen a wizard work things out like this, simply by looking and touching; but Harry had long since learned that bangs and smoke were more often the marks of ineptitude than expertise.
    Dumbledore stepped back from the cave wall and pointed his wand at the rock. For a moment, an arched outline appeared there, blazing white as though there was a powerful light behind the crack.
    ‘You’ve d-done it!’ said Harry through chattering teeth, but before the words had left his lips the outline had gone, leaving the rock as bare and solid as ever. Dumbledore looked round.
    ‘Harry, I’m so sorry, I forgot,’ he said; he pointed his wand at Harry and at once Harry’s clothes were as warm and dry as if they had been hanging in front of a blazing fire.
    ‘Thank you,’ said Harry gratefully, but Dumbledore had already turned his attention back to the solid cave wall. He did not try any more magic, but simply stood there staring at it intently, as though something extremely interesting was written on it. Harry stayed quite still; he did not want to break Dumbledore’s concentration.
    Then, after two solid minutes, Dumbledore said quietly, ‘Oh, surely not. So crude.’
    ‘What is it, Professor?’
    ‘I rather think,’ said Dumbledore, putting his uninjured hand inside his robes and drawing out a short