Inert gas asphyxiation lacks oxygen and consists of an asphyxiant gas (one or more of argon, nitrogen or carbon dioxide), causing the animals to lose consciousness. Argon and nitrogen are important components of a gassing process which seem to cause no pain, and for this reason many consider some types of controlled atmosphere killing more humane than other methods of killing. However, "stunning" is often done using carbon dioxide. If carbon dioxide is used, controlled atmosphere killing is not the same as inert gas asphyxia, because carbon dioxide at high concentrations (above 5%) is not biologically inert, but rather is toxic and also
Hammer Historical Collection of Incandescent Electric Lamps William Joseph Hammer started to collect incandescent light bulbs from 1879 while they were being developed in the Edison laboratory in Menlo Park, New Jersey. He was an associate of Thomas Edison and in his engineering career he was able to collect early filament electric light bulbs from Edison and others because of his association in the field. The Hammer collection is the most comprehensive collection of incandescent electric light bulbs known in the world. It shows the technology development of the filament electric light bulb during Thomas Edison's lifetime. Hammer's incandescent light bulb collection from around the world was