C1151 Ashes to Ashes
"Ahem, ahem, I spend most of my time practicing my martial arts. What kind of books are you reading?! It's useless! Don't you know that?" Qin Yuan explained awkwardly.
"Idiot! The research on magnetic fields has existed since ancient China. It can be traced back to the Warring States Period. At that time, there was a saying that five stones were used to treat illnesses