Tao Zhu
By the early years of the Daoguang Emperor's reign, the pernicious influence of opium had spread all across China, leading to a serious outflow of silver bullion and a society wide crisis. In 1838, Huang, by now Minister Herald, presented the emperor with a petition entitled "Plug the leak firmly to grow the country" (严塞漏卮以培国本疏 "Yán sè lòu è yǐ péi guó běn shū") - the leak in question being of silver bullion. In his memorial Huang asked the emperor to grant a one-year period of grace after which ordinary citizens who continued to smoke opium would face the death penalty while officials would face the same punishment with their offspring banned from sitting the imperial examination. The petition gained the support of officials including Lin Zexu and Tao Zhu, as well as praise from the emperor himself. On the eve of the First Opium War, Huang knew that control of China's coastal regions was vital to the suppression of the opium trade. He made two trips to Fujian Province and presented the emperor with a map showing suggested coastal defences, the "Hǎifáng túbiǎo" ().