This wall was tough. Ethan had already cast Scourgify on it 3 times. He sighed. Might as well try it once more. "Scourgify!", he practically shouted at the unforgiving wall. He dared to open his eyes. Yes! It had finally worked. Now, onto some more windows. Professor Knox had said the same effect of Vitrumonia could be accomplished by using both Scourgify and Poliotus on the glass. Mustering his concentration once again, "Scourgify!" Well, the glass was cleaner than before. Making the S movement with his wand, "Poliotus!" Ah. Now the window was truly clean.