Mari and Waka plan on making a cake for their friend, but plans fall apart when Mari opens a mysterious book that sends her flying back in time where she ends up crossing paths with William Gilbert.
in other words, perpendicular to 
the ground, is called a dip circle,
en otras palabras, perpendicular
al suelo, se llama círculo de inmersión,
ou seja, perpendicular ao chão,
é chamada de bússola de inclinação.