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But there was another deadly element, white phosphorus!
Once exposed to air and if the temperature exceeded forty degrees, it would burn.
Suo Lun had purchased a large amount of white phosphorus, and it was all stored in oil barrels. He had pierced several holes in some barrels, and from the moment he left Tianye City, the whale oil was continuously leaking. Suo Lun was cunning, the leaking whale oil flowed from smaller barrels into larger ones, preventing detection.
Once eighty percent of the oil in the small barrels had leaked out, the white phosphorus could no longer be completely covered and would be exposed to air.
However, for white phosphorus to burn, besides contact with humid air, another condition was required: the temperature needed to reach forty degrees.