Complex sentence: An early Russian gear was designed by a Lieutenant Poplavko: the Edwards brothers in England designed the first British example, and the Morane-Saulnier company were also working on the problem in 1914.
Split into simpler sentences: An early Russian gear was designed by a Lieutenant Poplavko, and the Edwards Brothers in England designed the first British example. Finally, the Morane-Saulnier company were working on the problem in 1914.