"A light silver vapour should now be rising from your potion."
-- Severus Snape in Potions Class (OP12)
Effect: calms anxiety and soothes agitation
includes powdered moonstone and syrup of hellebore
The third line reads:
'"Add powdered moonstone, stir three times counter-clockwise, allow to
simmer for seven minutes then add two drops of syrup of hellebore."'
References from the canon
- Tricky potion which is O.W.L. standard, taught in fifth-year Potions(OP12). Creates a light silver vapor over the cauldron.
- If not mixed properly it can put someone into an "irreversible sleep."
- Rowling intentionally creates humor by contrasting the intended effect of this potion - peace and calm - with the ingredient hellebore, which sounds rather evil (and is very poisonous as a matter of fact) and with the troubles the students have making it. Harry is so tense he forgets to add the hellebore and gets a zero for the day.
"Potter, what is this supposed to be?"
"The Draught of Peace," said Harry tensely.
- It's possible that since Harry had been attacked by Dementors in August and was bothered by visions of the Dark Lord, Snape was teaching this potion in the hopes that Hermione would make some for Harry, since he knew she had made potions on her own in the past.