Inert gas In food packaging, inert gases are used as a passive preservative, in contrast to active preservatives like sodium benzoate (an antimicrobial) or BHT (an antioxidant). Historical documents may also be stored under an inert gas to avoid degradation. For example, the original documents of the U.S. Constitution is stored under humidified argon. Helium was previously used, but it was less suitable because it diffuses out of the case more quickly than argon. Inert gases are often used in the chemical industry. In a chemical manufacturing plant, reactions can be conducted under inert gas to minimize fire hazards or unwanted reactions.
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