translation.en: It had deep underwater microphones, or hydrophones, cabled to shore, all wired back to a central place that could listen to sounds over the whole North Atlantic.
translation.zh: 它有一个深水麦克风或者说一个水下测音器， 这一水下测音器用线连接至海岸， 所有线缆连接至一个中心，在那儿能监听 所有穿过整个北大西洋的声音。