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In Chamber of Secrets, how did Dumbledore know Harry and Ron were there?

‘However,’ said Dumbledore, speaking very slowly and clearly, so that none of them could miss a word, ‘you will find that I will only truly have left this school when none here are loyal to me. You will also find that help will always be given at Hogwarts to those who ask for it.’

For a second, Harry was almost sure Dumbledore’s eyes flickered towards the corner where he and Ron stood hidden.

Chamber of Secrets - page 195 - Bloomsbury - chapter fourteen, Cornelius Fudge

marked as duplicate by DVK-on-Ahch-To harry-potter Jun 3 '14 at 19:15

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  • 2
    homenum revelio – CandiedMango Jun 3 '14 at 14:58
  • 4
    "And if uh...anyone wants to find out about...some stuff...just...ask the spiders." - Hagrid, master of deciet – Zibbobz Jun 3 '14 at 15:00
  • This has uncanny similarity to the question on another scene when Dumbledore was in Hagrid's hut and knew Harry was near see scifi.stackexchange.com/questions/55889 "(film) At Buckbeak's execution scene, how was Dumbledore in on the plan that he wouldn't set in motion until hours later?" – b_jonas Jun 3 '14 at 15:36
  • just curious... homenum revelio is used to identify the number of humans right? Of course - Dumbledore could've correctly assumed it was Harry and Ron - but how would he know where they were inside Hagrid's house? How did his eyes flick towards them if he can't identify where they were? – mustard Jun 3 '14 at 15:39
  • @mustard Well he knows Harry has an invisibility cloak and that harry and ron love hagrid. Also you can "sense" where magic has been when you are powerful enough and looking for it. It could also be as simple as that was an empty space, he heard faint breathing (as he would be listening for it) and i believe at one point even lucious came close to discovering them. I would write up an answer but rep cap and all :P. – CandiedMango Jun 3 '14 at 15:46

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