Other manufacturers used various materials as an insulator, including:ĬJ Gayler patented the fireproof double chest in 1833 that was created of two boxes with air in between as an isolator. That year, Jesse Delano coated inner safes walls with a mixture made of alum, clay, mica, lime, potash lye, and plumbago. The first iron safes occurred on the market in the 1830s. In the 15th century, merchants preferred oak chests banded with iron. Later, many feudal lords protected their papers in specially built underground vaults. After numerous unsuccessful attempts, they decided to develop a protective device for that purpose.įor instance, Julius Caesar kept his valuable records in iron boxes before concluding that this metal was a good conductor of heat and useless for protection against fire. Ancient people often had a problem protecting important documents and valuables from the fire.
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