These plantes are moste efficacious in the inflaming of the braine, and are therefore much used in Confusing and Befuddlement Draughts, where the wizard is desirous of producing hotheadedness and recklessness ...
Harry Potter and the Order of the Phoenix
I guess these three words ('plante', 'moste' and 'braine') might be the old version of 'plant', 'most' and 'brain'. But I haven't found any evidence. Have I gotten it right? Are these old-fashioned words?
Update: The quote above was excerpted from one of his Potions books that Harry was reading.