The document summarizes the use of chemical weapons, specifically gases, during World War 1. It describes how the Germans were the first to use chlorine gas in 1915 against French soldiers. It also provides details on how gases were deployed to clear out trenches and obliterate opposing armies from the air or by spraying. Production figures from World War 1 indicate Germany produced the most chemical agents totaling over 99,500 tons, including large amounts of chlorine and phosgene. The document also classifies different types of gases and provides examples of their effects, such as mustard gas causing blistering and chlorine destroying respiratory organs.