The third class for the afternoon was potions. Study groups were given potion raw materials and an instruction sheet. The sheet had a logic puzzle that Wei-Hwa whipped through which explained how to group the chemicals together. Eight chemicals were paired up and produced green (1939), purple (1938), pink (1937), and, heh, something that we didn't quite know what it should be. He'd just poured the liquides together and nothing much had happened. So we poured more in, and it was vaguely yellow or brown. The TA for the class ("Chris") suggested we agitate the mixture -- woosh, a reaction. Good thing we didn't put the top on the bottle. After several minutes the foam harden up. Fortunately for us there were house elves in the classroom to take care of cleaning up from our lesson.
Oh, the book! In our first class we received two copies of our textbook. The book was about 130 pages long and filled with useful information for wizards: a chapter about magical creatures, some notes about potions and spells, a long section on cryptonamy(?). Many puzzles required bits of knowledge from the text and I thought this was a very clever way to give it to teams, er, study groups
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