《南史·列传·卷七十二》
冲之改造了铜制机械，于是车子随便转动，指示方向却始终如一，自马均以来还没有过他这样的巧匠。
冲之改造铜机，圆转不穷，而司方如一，马钧以来未之有也。
Chongzhi modified the copper mechanism so that the car could turn casually, but the direction indicated was always the same, and there had been no craftsman as skillful as him since Ma Jun.
<s>[INST] Kindly elucidate the central themes in this passage in English: 冲之改造铜机，圆转不穷，而司方如一，马钧以来未之有也。 [/INST] Chongzhi modified the copper mechanism so that the car could turn casually, but the direction indicated was always the same, and there had been no craftsman as skillful as him since Ma Jun.</s>
Kindly elucidate the central themes in this passage in English: 冲之改造铜机，圆转不穷，而司方如一，马钧以来未之有也。
user
Chongzhi modified the copper mechanism so that the car could turn casually, but the direction indicated was always the same, and there had been no craftsman as skillful as him since Ma Jun.
assistant