Li Chengan, a modern materials science graduate student, soul-crossed into the twenty-fifth year of Jian'an, becoming the sixteen-year-old young master of Shiquan Fort in the borderlands. The granary in the fort was bottoming out, yet grain-collection documents grew heavier year by year. Starting from a pinch of bitter salt, he purified fine salt to trade back life-saving grain, and bolstered the fort's foundation with lime, an iron workshop, and new rules for a hundred men. Going to Hedong again, he incorporated disbanded former soldiers, picked apart accounts item by item with the grain merchant Zhang in Puzi Market, suppressed covert accounts and lowered prices, and ultimately negotiated for four hundred and fifty shi—two hundred and twenty shi loaded onto carts, with the remaining grain transported separately and converted into vouchers. On the night when grain sacks piled up like walls, he set up double sentries, sleeping beside the carts. Four hundred and fifty shi was the lifeblood keeping three thousand people alive for over a month more.