translation.en: They had put in underground sewer pipes, and as a result, one of the great scourges of the late 19th century, waterborne diseases like cholera, began to disappear.
translation.zh: 也安装了污水管。 因为这一发明，19世纪末的一大灾难--- 水传疾病例如霍乱，开始逐渐消失。