Gas chamber carbon monoxide as the lethal agent. Sometimes a box filled with anesthetic gas is used to anesthetize small animals for surgery or euthanasia. 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
Lawn mower powered by an internal combustion gasoline engine. JP Engineering of Leicester, founded after World War I, invented the first riding mowers. This went hand-in-hand with a booming consumer market for lawns from the 1860s onward. With the increasing popularity of sports in the mid-Victorian period, the lawn mower was used to craft modern-style sporting ovals, playing fields, pitches and grass courts for the nascent sports of football, lawn bowls, lawn tennis and others. The rise of Suburbanisation in the interwar period was heavily influenced by the garden city movement of Ebenezer Howard and the creation of the first garden