Combining Arithmancy and Ancient Runes, Vizet derived the complete potion-brewing process.
When Professor Snape saw Vizet put down his notebook, he raised an eyebrow and asked, "Finished already?"
"Professor Snape, right now I've only completed a prototype..." Vizet said honestly. "We can brew one potion first and test the final effect."
Professor Snape stood up. "How many portions of Alioth Leaves are needed in one potion?"
Vizet said, "Six portions of Alioth Leaves are needed."
"And Demiguise Feather?"
"Eight portions."
"And ambergris?"
"Five portions of ambergris are needed."
"Five portions..." A sharp glint flashed in Professor Snape's eyes, as if he were calculating something. At last, he nodded and said, "Begin!"
After saying that, he stopped in front of a shelf, picked up a Glass Jar containing earthworms, and walked toward the Horklumps at the side.
As he started brewing the potion, Vizet was also thinking about a question.
He realized that the Potion Ingredients Professor Snape had asked about were all relatively precious Potion Ingredients, such as Demiguise Feather, each of which sold for five Gold Galleons;
There were also Alioth Leaves, each of which sold for four Gold Galleons; to say nothing of the most expensive ambergris, which cost three hundred Gold Galleons per ounce;
Even if he calculated only the prices of these three Potion Ingredients, the potion that could make someone recall fear cost at least one thousand five hundred and sixty-four Gold Galleons...
Vizet remembered Professor Snape mentioning something: Frog Brain Pulp was cheap, but Frog Brain Pulp that possessed the magical property of "fear" could replace certain expensive Potion Ingredients;
It was precisely for this reason that Professor Snape had said "they should be very pleased to contribute to the school"...
Which meant Professor Snape had assessed the cost price of the potion before