At the end of Qing Dynasty, China people smoked opium everywhere. So the Qing Dynasty sent Lin Zexu to Guangzhou to ban smoking. When Lin Zexu arrived in Guangzhou, he found that foreigners not only exploited China people on opium, but also plundered some basic trade.

At that time, in foreign trade, the Qing dynasty mainly imported cloth from some western countries and exported porcelain and tea, but such trade made the Qing officials suffer a lot. It turned out that in the trade with foreign businessmen, the Qing Dynasty always suffered: when transporting cloth, foreign businessmen often encountered wind and waves on the way, the cabin would be flooded, and the quality of cloth soaked in seawater would be damaged.

However, they bullied honest officials and couldn't find out. Whenever the cabin is flooded, these foreign businessmen will stop at some hidden islands and dry the cloth soaked in seawater before arriving at the port. The dry cloth was difficult to check for a while, so the honest official had to collect it, but the quality of the cloth would be greatly reduced if it was flooded.

Although the porcelain and tea exported by the Qing Dynasty were bundled with straw, many of them were broken when they went abroad after stormy waves, and the tea was wet, so foreign businessmen tried every means to lower the price.

After Lin Zexu came to Guangzhou, he investigated opium and watched foreign businessmen let glistening silver dollars flow into foreigners' pockets. It was heartbreaking, but there was nothing he could do.

One day, Lin Zexu accidentally picked up a mung bean in the hut. He looked at mung beans and suddenly had a plan. When he arrived at the yamen, he summoned foreign businessmen and announced: "In the future, China will import foreign cloth and mung beans at the same time. When loading, you must arrange a row of mung beans at intervals. When the ship arrives at the port, it will be delivered in advance, otherwise the fabric will be rejected. "

Then, Lin Zexu summoned local businessmen to announce: "When exporting porcelain, mung beans must also be placed in the cracks of porcelain, otherwise they are not allowed to be exported."

Shortly after Lin Zexu announced the regulations, a group of British businessmen's cargo ships docked. Lin Zexu personally inspected the goods. He asked, "Was there any water in the cabin?" The British businessman drew a cross on his chest and said, "Thanks to God, the journey was peaceful and there was not a drop of water in the cabin."

Lin Zexu smiled and ordered officials to dump mung beans. I see many mung beans have sprouted. Lin Zexu picked up a mung bean sprout and asked seriously, "If there is no water in the cabin, how can mung beans germinate?" British businessmen are speechless and can only accept fines according to regulations. The British businessman thought: When China porcelain is shipped out, it is often broken. When the time comes, tit for tat will definitely get the money back.

When the ships from China arrived at the British port, British businessmen flocked to try to recover the losses in the port of China. However, these foreign businessmen were disappointed. The porcelain is very well preserved, and nothing is broken. It turned out that Lin Zexu sprinkled water on the porcelain bottle containing mung beans, so that once the mung beans germinated, all the gaps in the porcelain bottle could be filled. In this way, no matter how big the storm is, the porcelain will be safe and sound, and these germinated mung beans can also be sold as feed, killing two birds with one stone. The wishful thinking of the British businessman fell through.