All the students began the first step: preparing their ingredients.
Snape watched everyone below prepare their ingredients with practiced ease and gave an almost imperceptible nod.
After all, these students had been practicing their knife skills with kitchen ingredients since their third year.
After three years, they were more than qualified to work arranging fruit platters in the Muggle World.
Before each step, Neville muttered something under his breath.
"Two turns clockwise."
"Silverleaf, add three seconds before the temperature reaches boiling point."
Like a snake, Snape glided silently down the aisle.
He stopped behind Neville.
He stared at the cauldron bubbling with pale blue bubbles.
"The heat is far too low, Longbottom."
There was undisguised mockery in Snape's voice.
"Are you planning to give the silverleaf a lukewarm bath at that temperature?"
"That could prevent the active ingredients from being released sufficiently, leaving you with a pot of wastewater."
Neville immediately turned up the heating rune underneath.
"If I raise it by three degrees."
Neville spoke as he watched the boiling potion.
"I'll need to shorten the clockwise stirring time by seven seconds."
"Otherwise, extraction at an excessive temperature will alter the calming effect."
"It'll turn directly into delayed paralysis."
Snape stopped dead just as he was about to turn away.
He reassessed the boy before him.
For the first time, genuine interest appeared in those hollow eyes.
"That assessment."
Snape spoke slowly.
"Which piece of extracurricular wastepaper did it come from?"
Neville took a deep breath.
"An old potions notebook passed down in the Longbottom family."
"Combined with the discussion of postwar neural spasms in last semester's revised textbook."
"But I used the neurotransmitter analogy theory in the current textbook to reinterpret it and work through the derivation again."
The entire classroom fell silent.
Only the bubbling of potions