Gas chamber Gas chamber A gas chamber is an apparatus for killing humans or other animals with gas, consisting of a sealed chamber into which a poisonous or asphyxiant gas is introduced. The most commonly used poisonous agent is hydrogen cyanide; carbon dioxide and carbon monoxide have also been used. Gas chambers were used as a method of execution for condemned prisoners in the United States beginning in the 1920s and continue to be a legal execution method in three states. During the Holocaust, large-scale gas chambers designed for mass killing were used by Nazi Germany as part of their genocide program.
Electric bus and unpleasant exhaust fumes. However, improvements were made to the gasoline-powered car that caused the electric car to lose some momentum. The hand crank was soon replaced with an electric starter and gasoline-powered vehicles became more affordable. Gasoline cars soon overcame the popularity of electric powered vehicles. By 1935, electric cars practically disappeared. It was not until the 1970s when a gas shortage hit, causing gas prices to soar, that electric cars entered back into the marketplace. Gasoline-powered cars still remained more popular due to better performance and reliability. The 1990s saw electric cars made more popular as societal concern