That day, Goaskin and Umber went to the clay pit. Goaskin wanted to show Umber the differences between earth sprites, depending on the ground, and Tiel, his other apprentice, showed neither talent for nor interest in dealing whith those elementals, so he had stayed home.
When they came back, they heard strange noises from the chamber Goaskin called his study; it was a quiet place high up in the tree. Not so quiet right now. Goaskin sent Umber to the apprentices' chamber and continued up the rounded stairs to investigate.
He found Tiel staring at a whizzing creatue. A sprite, moving quickly and erratic, changing colour incessantly. Where it touched the smooth bark of the floor, it left ashes in some places, and coaxed buds and blooms from others.
"Tiel, don't look at it!"
He pulled the boy behind him and focussed on the jinking sprite, trying to calm his thoughts and neutralise it. He was not calm enough, but it evaporated in a discharge of magic that turned the small vase of flowers in its niche into a handful of green sand.
When he was sure it was gone, Goasking took a deep breath.
"Tiel," he said sternly, "did you really summon a chaos sprite?"
"Yes!" Pouting, what he probably thought defiant. At least he had noticed his teacher was angry.
"Why?"
"Because it said it's possible!" Goaskin picked up the journal Tiel waved at. "I understood the feeling it described, and it said they could do anything!" Way too much excitement in there.
Goaskin sighed. "Tiel, they are nearly impossible to control, and most of everything is not something you want to happen." His voice grew sharper than Tiel ever had heard. "Do you want to be turned into a toad? Or be teleported ten paces below the earth? Or have your mind thrown into limbo, leaving your body with less brains than a cabbage? If so, summoning a chaos sprite is a good idea, but do. Not. Do. It. Here."
After a moment's hesitation, the boy started a litany of justifications. "But it almost did what I wanted it to!"
Goaskin listened, leafing through the journal in search for a certain passage, waiting for his cue. "But it would have said if it was dangerous!"
Goaskin shoved the book into the boy's face. "Read!"
"Do... not do this... and... um."He looked down at his feet. "What you said, teacher."
"Right. Next time, read all the way through, boy."
Tiel nodded hastily and ran off.
Goaskin sighed, weighing the book in his hands. After short consideration he decided not to stash potentially dangerous books somewhere where his apprentices could not reach them. Tiel, for one, might get more curious. Tiel would learn to be careful, without causing a disaster first. Probably.