"Since I'm the one handling the details of the lessons..." Vizet was a little curious. "Headmaster Dumbledore, then why did you ask me to stay..."
"That magic that helped Harry ease his pain..." Dumbledore asked with great interest. "If I remember correctly, its name is the 'Silent Wound Spell'?"
"Yes!" Vizet took a notebook from his pocket. "It's a spell I invented after studying 'Consensus' Magic."
Dumbledore pushed the plate of Cookies forward, as if striking a deal with Vizet, and opened the notebook Vizet had pushed over.
"Using 'if it hurts, cry out' as the principle..." A smile hung at the corners of his mouth. "Turning that principle around..."
"It becomes a spell that eases pain... and the casting difficulty is quite low... A rather interesting conclusion, and a rather fascinating line of thought!"
"The incantation is 'Sleepiness Spreads.'" Dumbledore looked up at Vizet, then back at the contents of the notebook.
"The principle is 'yawning is contagious'... It can trigger a chain reaction of muddled awareness and guide people into a light sleep..."
"That often happens in History of Magic class..." Vizet explained with a smile. "Of course! It also happens very easily in the Common Room after ten at night."
A portrait behind Dumbledore spoke. "Albus, what is the name of this spell?"
"Dilys..." Dumbledore answered. "This spell is called the 'Mass Hypnosis Spell.'"
The "Dilys" Dumbledore mentioned was, in full, Dilys Derwent. She had not only been a Headmaster of Hogwarts, but also a healer at St. Mungo's Hospital for Magical Maladies and Injuries;
Dilys Derwent had also made considerable contributions to St. Mungo's, so her portrait was hung not only in the Headmaster's Office, but also on the wall of St. Mungo's waiting room.
"Mass Hypnosis Spell? Silent Wound Spell?" Dilys Derwent pressed. "The effects