The Arbalète sauterelle type A allowed bombs to be thrown into trenches beginning what was called what?
Trench warfare Trench warfare is a type of land warfare using occupied fighting lines consisting largely of trenches, in which troops are significantly protected from the enemy's small arms fire and are substantially sheltered from artillery. The most famous use of trench warfare is the Western Front in World War I. It has become a byword for stalemate, attrition, sieges and futility in conflict.
Zone libre The zone libre (] , "free zone") was a partition of the French metropolitan territory during World War II, established at the Second Armistice at Compiègne on 22 June 1940. It lay to the south of the demarcation line and was administered by the French government of Marshal Philippe Pétain based in Vichy, in a relatively unrestricted fashion. To the north lay the "zone occupée" ("occupied zone") in which the powers of Vichy France were severely limited.