Who invented the fire extinguisher?

In the late 19th century, Alexander Laurent, a graduate of the St. Petersburg Polytechnic Institute, arrived in Baku to work as a chemistry teacher. At that time, Baku, a rapidly developing city with oil fields, often suffered from fires due to the imperfect technology of oil extraction. Observing yet another fire, Alexander Grigorievich pondered the creation of a device capable of extinguishing flames in the first minutes. He noticed that oil does not extinguish well with water and decided that something else needed to be used.

Soon, Laurent had a revelation. There are two versions of how this idea came to him. According to the first, he saw how a foamy wave on the shore of the Caspian extinguished burning oil. In the other version, the idea of foam for extinguishing fires came to him in a tavern when he looked at the beer foam in a mug. In any case, Laurent realized that foam should be used to extinguish fires.

On May 25, 1904, Laurent submitted an application to the Russian Patent Office for a "Method of Fire Extinguishing." In the application, he described that the burning surface is covered with an aqueous solution of known extinguishing substances not in the form of a liquid, but as a semi-liquid porous mass. He proposed using licorice, albumin, glue, and soap root as foaming agents. Laurent also noted that saturating the foam with a non-combustible gas increases its fire-extinguishing properties.

Thus, the production of the first fire extinguishers began in the country, organized by the Moscow firm "Eureka-Bogatyr." Initially, they supplied firefighters, and then they began to spread throughout the state. If you are at work, look around; perhaps a descendant of Laurent's fire extinguisher is hanging nearby.