《天工开物·中篇·冶铸》
自从全国各地都进贡金属铜给夏禹铸成象征天下大权的九个大鼎以来，冶铸技术也就日新月异地发展起来了。
九牧贡金，用襄禹鼎，从此火金功用日异而月新矣。
Since the time when copper metal from all places of the country was contributed to Xia Yu to cast the nine large cauldrons symbolizing the supreme power of the world, casting technology has also developed with each passing day.