The compasses released, how could Yu Ziqing not tamper with them?
Even if he couldn't artificially control the result of the compass's judgment, leaving a small measure to monitor whether someone disassembled the compass was incredibly easy.
He sent out less than ten compasses in total, and he always kept track of who held each compass and in which direction it went.
One compass self-destructed due to disassembly, and Yu Ziqing could easily guess who was responsible.
When the compasses were sold, it was made very clear that they were integrally formed. Damaging the internal power would lead to a loss of control.
Moreover, with their high value and scarcity, less than ten compasses would take more than a year to circulate among all those needing inspection.
As for Song Chengyue, the added value of the compass far exceeded its inherent value.
