Neither the miner nor the logger can be dispensed with, any more than can the chemist at the factory or the worker in the oil field -- paraffin being a by-product of petroleum.
伐木工人和矿工都不能省略，至多却不比工厂里的化学家和油田里的工人更重要——石蜡是石油的副产品。
3
Benzene, a chemical compound refined from crude oil, was found to cause leukemia in 1928 by two Italian doctors who detected the cancer in a worker exposed to benzene for five years.