Complex sentence: The Lebel rifle was created to gain a competitive advantage by using, for the first time in firearm history, smokeless gunpowder: it had just been invented in 1884 by French chemist Paul Vieille (1854--1934).
Split into simpler sentences: The Lebel rifle was created to gain a competitive advantage by using, for the first time in firearm history, smokeless gunpowder. It had just been invented in 1884 by French chemist Paul Vieille (1854--1934).