Unrelated to the article directly, but a pretty fascinating story of salt:<p><i>By the end of the 2nd century CE, workers had devised a system of leather valves and bamboo pipes which drew up both brine and natural gas, which they burned to boil the brine (the technology they developed for the bamboo piping was eventually applied to household plumbing).</i><p><a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Salt_in_Chinese_history#Ancient_China_and_the_early_empire" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Salt_in_Chinese_history#Ancien...</a>