Lesson Three

As the students were finishing to practice, Ambrosius walked to the center of the classroom and said: "Good work, everyone. As far as I have seen, most of you have succeeded to cast the spell correctly. For your effort, I give 20 points for Slytherin and 10 for the three other Houses. Now please gather around as I wish to show you the limits of the Knock-back Jinx before we run out of time. A few minutes later, the students had formed a perfect circle around him. "As you have all pointed out in your homework, this particular charm is not the most effective one when dealing with the Dark Arts, and you are about to witness some of the reasons why. I will need someone to help me with this demonstration." He gazed across the audience. "Miss Frey, if you would please step up and cast the Knock-Back Jinx on me. Don't worry, I won't hurt you."

Kim stood up from where she is lying and heard Richard approached towards her. "Are you all right? I'm sorry, once the connection broke I couldn't control the spell anymore." he said, concerning on her downfall. "Yeah, I think I'm alright, just a bit of tired."

Professor Umbranox started to give instructions to them, saying that he'll demonstrate how the Knock-back jinx isn't as great as it seems. All of them formed a circle, centering the professor, trying to listen very carefully.

"Miss Frey, if you would please step up and cast the Knock-Back Jinx on me. Don't worry, I won't hurt you." he stated. Kim, trying to recover from the downfall, nodded and started to walk in front of him. She raised her wand, pointing at the professor and casted, "Flipendo!"

"Miss Frey, if you would please step up and cast the Knock-Back Jinx on me. Don't worry, I won't hurt you." Professor Umbranox had said. Keith watched Kim make her way towards him, then point her wand at the Professor and cast the spell. Keith stood there anxiously, waiting to see how the Professor would defend himself, while wondering what would happen to Kim.

"Expelliarmus" Ambrosius uttered, aiming at her wand, as soon as he heard her pronounce the incantation. With a luminous jet of red light, the charm precisely hit its target, that immediately flew out of the girl's hand and landed on the cushions without a sound. Slowly walking towards her, he pointed his wand at hers. Accio, he thought and the object levitated directly into his hand. "Here is your wand, miss Frey." he said, giving it back to her. "As you have just seen, and as some of you have rightly written in your homework assignment" he pursued addressing the class, "even though miss Frey's spell was executed very well, a simple Disarming Charm was enough to negate it. That is one of the elements showing that the Knock-Back Jinx may be ineffective, especially when facing relatively advanced witches or wizards."

"We will now proceed to another limit of the jinx." he pursued as he had walked back to the center of the classroom. "Thank you, miss Frey, you did very well." His glance swept the group in search of a new student. "Mister Parker, if you would be kind enough to assist me with the next demonstration. The instructions stay the same. You can cast the spell whenever you feel ready."

"Mister Parker, if you would be kind enough to assist me with the next demonstration. The instructions stay the same. You can cast the spell whenever you feel ready." Professor Umbranox said. Keith reached for his wand and walked over to him. He pointed his wand at the Professor, hoping he wouldn't mess this up in front of the whole class. "Flipendo!" Keith said as clearly as he could, his wand still pointing at Professor Umbranox.

"Flipendo" Ambrosius heard and a jet of barely visible silver light burst out of Keith Parker's wand, rapidly flying towards him. "Protego" he pronounced with his usual calm voice while waving his wand. A transparent bright blue shield instantly surrounded him. As soon as the spell reached the magical barrier, it simply rebounded and headed back towards its caster. Hitting the boy directly in the chest, his own charm violently knocked him down to the ground.

"I apologize for that, mister Parker. You were the only one who still hadn't experienced the effects of the spell. However, the brutality of your fall is but a proof of the quality of your spell." he complimented the student as he was getting back to his feet. "As some of you may have guessed, the spell I performed is a Shield Charm. It is relatively advanced magic and you won't therefore be learning it until later years. The point was to show you that this charm is also a very effective way to defend yourself against a Knock-Back Jinx." He marked a short pause, looking at his students, then pursued: "Well, let us move on to the last experiment. Thank you, mister Parker. Mister Macgonagall, if you would please help me with the final demonstration. You know what you have to do."

Keith felt a rush of excitement running through him as he was flown backwards. He got back up, as Professor Umbranox complimented him. "As some of you may have guessed, the spell I performed is a Shield Charm. It is relatively advanced magic and you won't therefore be learning it until later years. The point was to show you that this charm is also a very effective way to defend yourself against a Knock-Back Jinx." Professor Umbranox had said. Keith nodded, he knew it was true.

Bill woke up from deep sleep he had fallen in. He had strange ability to wander off so hard that no one could wake him up and last night he did not get any sleep. "Sorry professor I would go to that right away". Bill knew he had to trow knock back jinx at the professor but since he never did it it could be really tough. Bill walked to the professor and stood in the wand ready position. He gathered his concentration and was prepared to do the jinx. He new that incantation was flipendo so he figured in his mind how he casts the spell and said "Flipendo". Unfortunately nothing happened, he got little blushed and thought everyone will laugh at him. He forget about it and said one more time "Flipendo" but this time only small amount of smoke appeared form his wand. "huh better than the last time" Bil said. He tried to forget everything and clear his mind he put his whole mind into it and said "FLIPENDO!" and this time small silver light appeared from his wand, but light was barel visible, Bill felt strange tickling in his fingers and light traveled to the professor Umbranox. Bill new that he succeeded the spell this time

Ambrosius patiently waited as William Macgonagall seemed to have issues casting the spell. However, at his third attempt, he succeeded, sending a silver ray of light towards him. This time, Ambrosius did nothing to defend himself, and the charm hit him directly in the chest. Under the shock, he was forced to move back a few steps, but stayed on his feet. "Very well executed. However, as you have noticed" he pursued looking at his students "I wasn't knocked down to the ground. Considering that there was nothing wrong with mister Macgonagall's spell, can anyone tell me why is that and what limit of the Knock-back Jinx does it show?"

"I wasn't knocked down to the ground. Considering that there was nothing wrong with mister Macgonagall's spell, can anyone tell me why is that and what limit of the Knock-back Jinx does it show?" Professor Umbranox asked. "Is it because you're much more experienced than us?" Keith asked. "Or maybe because you were expecting the spell?"

"Is it because you're much more experienced than us? Or maybe because you were expecting the spell?" he heard one of the students ask. It was Keith Parker, the Gryffindor who had helped him with the second demonstration. "That may be true in other situations , but not in this one. You see, since I did nothing to defend myself, my experience is of small matter here. And I also did not try to physically resist being knocked down, so the fact that I was expecting the spell didn't in any case diminish its effects. It just may have helped me be less surprised by them." He swept the students with his gaze, waiting for someone to suggest another idea.

Keith had ran out of ideas, but maybe some of the other students had something in mind. But Professer Umbranox was right, Keith didn't think of that. But it was definitely a contributing factor. He tried thinking of some more ideas that could explain why Professor Umbranox hadn't been knocked down by the Knock-Back Jinx.

"Professor, I think that the reason why it didn't work is because Knock-back jinx isn't that powerful enough to knock down all the enemies around. It also depends on how big the thing or person you want to 'knock back'," Kim answered, trying to break the tension.

"Very good, miss Frey. One of the main factors that determine the effectiveness of the Knock-Back Jinx is the weight of the object or the person you are trying to perform it on. Since I am an adult, and considering your magical abilities, it is quite difficult for you to knock me down, whereas the charm was quite useful when performed on your fellow students. That deserves five additional points for Slytherin." he announced, looking at Kim Frey. After a brief pause, he pursued, addressing the class: "Considering that limit of the jinx we're learning, can someone give me one or two examples of magical beings the spell would we particularly ineffective against?" he asked, glad that his pupils were actively participating.

James suddenly remembered that he wrote about that aspect of the Knock-Back Jinx in his homework assignment. While trying to recall what example he used to illustrate it, he glanced around to see if anyone else had an answer. He didn't like being the center of attention, and wanted to avoid getting noticed if that was not necessary. However, after a few moments, as no one seemed to have an idea, he timidly raised his hand and waited for Professor Umbranox to give him the permission to speak. "A troll maybe?" he asked. "Or a giant?" he added, noticing one on one of the paintings the professor had hung all around the room.

"Yes, those are two fine examples. Well done, mister Riddle. Five points for Ravenclaw. As you can see, despite being quite relatively simple to learn and sometimes quite useful, the Knock-Back Jinx is far from being the most effective weapon you can use when battling the Dark Arts. However, that is not a reason to consider that it is not important to know it, and I would ask you to keep practicing after class until you are able to perform it flawlessly."

He looked at his watch. There were only a few minutes remaining. "Well, that will be all for today. If you have any questions, you can come see me anytime in my office, which is located just on the stop of these stairs." he said, showing them the staircase behind his desk. "I have decided not to give you any homework for next time so that you can fully enjoy the holidays. I'll see you after the break." he finished, and watched as the students were rapidly moving to the back of the classroom to take their bags.