裨海紀遊/Travel Via A Small Sea (Sulfur Mining Diary)
In 1696 (Kangxi 35), a gunpowder warehouse in Fujian exploded. About 300tons of raw materials were lost. It became necessary to get a new supply from elsewhere. Taiwan was known for its availability at the northern part of the island. Most people retreated from going to Taiwan to mine the sulfur because it was considered a very dangerous journey and hard job. However, Yu Yong-he, an adventure lover, voluntarily took up the tough job.
The next year 1697 in spring, Yu departed from China with his artisans. They arrived at Tainan on Feb. 25th, 1697. They stayed at Tainan for two months for preparing the necessary items to be used in mining sulfur. The prepared items were sugar, cloth, and oil. Sugar drinks could be used as an antidote against sulfuric air, cloths could be used in the exchange of goods with Ketagalan people, and oil could be used in sulfur refining. These kinds of stuff were transported to northern Taiwan by boat. On the other hand, Yu and his people went northward by ox carts. It took about two months for them to arrive at Beitou from Tainan. The road condition was very bad and also they had to go across several rivers. It was a very tough journey. Yu described all what he saw and heard in his diary in detail.
After arriving at Beitou, they started mining the sulfur. It was not smooth because many of his workers got sick due to their incompatibility with the environment. The sick workers were sent back to China, and at the same time, 60 new workers were sent to Beitou for finishing the whole work. He traded off his cloths with Ketagalan people against sulfur-contained ores, 7ft cloth for a barrel about 168kgs ore. He used 10kgs oil to boil about 540kgs ore. Ore of good quality could yield about 300kgs sulfur, the inferior one was only about 120kgs.
In October 1697, Yu and his people left Taiwan for China with a satisfactory volume of sulfur. The rational quantity should be more than 300tons, more than the volume exploded.

