PS/SS question

[Amanar]

No: HPFGUIDX 94481

I've been re-reading book 1 and was wondering - when Harry meets 
Quirrel in the last chamber ("The Man with Two Faces" chapter)
Quirrel tells Harry that Snape suspected him from the very beggining 
and that he was already onto him when Harry eavesdropped on them in 
the forest (haven't got the book with me so can't give an exact 
quote).

What exactly was Snape suspecting Quirrel for? Did he know that 
Quirrel was after the Stone, or did he suspect Quirrel wanted the 
Stone to aid Lord Voldemort?

--Amanar.


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