Lilly instantly put up her hand. She liked volunteering for things. She'd heard of that spell, but what did it do? Then the Professor told them. Water, that was it. She was volunteering to fill vases with jets of water? That suited Lilly. She'd never used the spell, but she could try anyway. It couldn't be that hard, saying the incantation and filling up a vase with water. She put the best vase away, of the two she'd done. One still looked very like a thimble.