C397 Dahu jail hearing(4)

The bronze mirror that could reflect everything in the cell would be hidden in a dark corner at the four corners of the cell. From somewhere, it would refract and shoot everything back through a small hole in the wall.

In that era, Gu Qingli could not help but admire the ability of using the copper mirror's refraction technique to its fullest.

After comparing it with each other for a while