Before the modern fire extinguisher was invented, people used all sorts of methods of fighting fires in homes-- including a fire extinguishing grenade.

Fire extinguishers have been used for almost 300 years. They have gone through various transformations as new chemicals and chemical combinations have been found. Many times the chemical used were found to be a hazard to people's health and so a different combination would be searched for.

One of the most interesting fire extinguishing devices throughout these few hundred years has been the fire grenade. This was a glass sphere filled with an extinguishing agent that was intended to be hurled at the base of a fire. The device was mainly filled with carbon tetrachloride, though some earlier versions had salt water. Carbon tetrachloride stopped being used in the 50's due to its toxicity.

Today there are numerous different chemicals used in fire extinguishers. There are dry agents, foams, clean agents and CO2, Class D, aerosol fire suppressors and yes, a modern version of the fire grenade.

The modern fire "grenade" is called a fire extinguishing ball and, like the original, is thrown into the fire. The ball self-destructs when in contact with fire and disperses a dry chemical to put the fire out, covering about five square meters. An advantage of these is the ability to place these anywhere in anticipation of a possible fire. The ball will destruct when there is a fire without the need for human intervention.

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