Today everyone knows what a flashlight is. It is not a big deal if you own one. However in the 19th century that was not the case. Thanks to David Misell around the end of the 19th and the beginning of the 20th century a small battery charged devices were introduced which could generate light in a short period. It was a real revelation. Preceding the flashlight and necessary condition to be developed was the battery with a dry cell. These batteries as we all know today use paste electrolyte therefore they are much safer than any other alternative.