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.
Vardar Offensive The Vardar Offensive (Bulgarian: Офанзива при Вардар ) was a World War I military operation, fought between 15 and 29 September 1918. The operation took place during the final stage of the Balkans Campaign. On September 15, a combined force of Serbian, French and Greek troops attacked the Bulgarian-held trenches in Dobro Pole ("Good Field"), at the time part of the Kingdom of Serbia (present day Republic of Macedonia). The assault and the preceding artillery preparation had devastating effects on Bulgarian morale, eventually leading to mass desertions.