Complex sentence: The British made early use of underwater listening devices called hydrophones, while the French physicist Paul Langevin, working with a Russian immigrant electrical engineer, Constantin Chilowsky, worked on the development of active sound devices for detecting submarines in 1915 using quartz.
Split into simpler sentences: The British made early use of underwater listening devices called hydrophones. The French physicist Paul Langevin, working with a Russian immigrant electrical engineer, Constantin Chilowsky, worked on the development of active sound devices for detecting submarines in 1915 using quartz.