Time for the second step.

But... as Helena looked again at the instructions... EWW! Clay? Why?

For some reason, she didn't like this step. But of course she'll do it. She did even worse things during Potions. Like killing those poor creatures last term. So... she moved the tank, so it stood on the desk right in front of her, and added the disgusting clay. Thirty centimeters, just as the instructions on the blackboard told her to add.

Step number two done.