Snape entered his potions room first and then gestured for Tom to follow him.
He brought out several vials and a chest. He also told Tom to prepare the cauldron, glass bottles, and other instruments. The chest opened in a staggered fashion, with several layers of small chests stacked on top of each other, each with dozens of compartments. Some of the compartments had a white mist coming out of them, as if some of the potions required special storage conditions.
Snape's chest must have been under an Undetectable Extension Charm, as he actually pulled out a large handful of fresh roses. Of course, roses in the hands of Potions Masters were not exactly the same as those used by ordinary people.
"Pluck the thorns from these roses, then dry them with the petals, grind them into powder and the essential oil is extracted with castor oil" Snape said.
The petals and thorns of roses can be used to make beauty remedies, perfumes and some love potions. Their extract, rose oil, could also be used to make magic potions, but I didn't know how it would be used in a Matalobos Potion.
Tom did as he was told, first removing the thorns from the roses with gloves and then baking them in the oven with the petals he had collected. After they dried, Tom put them in a mortar and pestle and ground them to powder.
All the while, Snape stood behind him with a frown, grimacing if Tom got out of shape, and when he was done, he walked over and took a good look at the powder Tom had ground.
"The drying isn't too bad, the thorns are completely dry. But next time remember to get the petals out of the way, some were gumming up. But the grinding is not enough and should be finer."
So Tom kept grinding. As he was grinding, he asked, "Professor, why don't we use magic for these repetitive tasks?"
Snape looked at Tom as if he were looking at an idiot and ignored him: it was too simple a question for him to explain.
If it could be replaced by magic, then why are you here, Tom?
During the second grinding, Snape did not stand idly by, but began to prepare the prepotion himself. He quickly chopped the daffodil root and moonflower, then added the wormwood infusion. A clear blue vapor rose from the cauldron as soon as the ingredients were added, but it took a few moments for it to turn into a homogeneous blue-green liquid. This was the ideal state for a simmering potion.
Next, Snape pressed the drowsy beans with his silver penknife, squeezed the juice out of them, and poured the residue into the cauldron with the valerian root, at which point the color of the liquid in the cauldron changed from dark brown to dark purple.
Then it was time for the hard work. Naturally, Snape turned his attention to Tom.
Tom ground the powder once more, and passed. After passing Snape's approval, he asked Tom to make a bottle of rose oil. He held the oil to the candle flame for a while, pulled the cork and smelled it.
"The oil is satisfying. Now you go and stir the potion counterclockwise until it's clear as water, and if you stir it wrong, you're good to go."
So Tom went back to stirring the potion.
And so Tom stirred the potion again until it was as clear as water.
By now Snape had almost finished brewing the rest of the potion. He glanced at Tom's preparations and nodded: Tom had been a great help, and without him the preparation of the potion would have been delayed by at least half a day, and Snape would have had to stay up all night.
Then the potions and powders were mixed, and with a quick flick of his wand, the liquid was soon swirling in the cauldron, as it shimmered with a haze of moonlight.
Snape glanced at the state of the potion and nodded in satisfaction as he saw that it was not much different from what was written on the paper. As was Snape's custom, the first time he reproduced a potion, he would follow the exact procedure on the paper. But then, Snape had to make his own optimizations, a habit he had since he was a student.
Tom had a small question in mind, and seeing that Snape seemed to be in a good mood, he asked, "Professor, how do you mix the ingredients for potions? How is it possible that that combination of ingredients can keep a werewolf sane during a full moon?"
"Yodel, this is not a matter for you to study. Research into potion materials and improving formulas are the goals of students in seventh grade and after graduation." Snape grew serious, "Each branch of magic is so vast and deep that it often requires a lifetime of effort. If you maintain an interest in Potions after your fifth year, go back and study the reasoning behind it.
Do you know how to measure the qualifications of a potions master?
It's not about how many potions he can create, or what he can do to improve existing ones, that's for wizards like me to worry about, as long as he can follow a recipe and make every potion mentioned in Potions class, he's a Potions Master.
A man's life is short and he can only concentrate on one thing."
Snape seemed to be in a very good mood, so he gave an unprecedented speech. When he finished, Snape looked at the Potions cauldron.
"And then it's time to wait." Snape announced that he was done for the day and would send a letter ahead the next time he needed Tom. Then he sent Tom away.
Tom left the room feeling a little tired, but the reward was not small: he saw that his Potions experience bar had gone up tremendously, about three times what he had gained in class.
He thought he was going to have to find a way to get a train back to London, but instead he saw Snape leave the room with a deadpan expression on his face.
Tom: "???"
To his surprise, Snape took him back to the Leaky Cauldron to the (Apparition)!
This was not something Snape could have done. But Snape said nothing to Tom, he walked straight through the doors of Gringotts: today he had come to collect his money.
Tom's life returned to normal.
After a long while, he opened the dusty Diary again, this time to get something out of Riddle.
"You're back" Said the Journal.
"I'm back" Tom said.
"I didn't think you were back" Said the Diary.
"I did take a long time. I needed time to digest your comments" Said Tom.
Diary: "..."
"I think you're right." Tom continued to write in the Diary, he intended to behave like a scoundrel, to trick Riddle into trusting him, then drain all the knowledge from the Diary and finally send it to Merlin when Riddle was void of knowledge.
Of course, Tom was a scum, and Riddle was a sea lord. This Riddle Horcrux has at least one life on his hands, if not more: his father's family, his uncle's family....
You could say he's taking revenge for the dead.