Mnemonic symbol: a balloon. The Queen of Hearts is disappointed by her balloons. She expected them to float upwards, but in the space station's bathroom, They float randomly in all directions.
哼
=
亨
+
口
:
In front of the engine ((e)ng1), Joseph Henry (亨) finally has the idea how to build his coil and exclaims "hurrah!", accidentally throwing away Hamlet's (h) mandarin (口) so Hamlet just says "humph!" (哼).