FIRE EXTINGUISHER. 25 



acid, but it is probable that anhydrous sulphuric would also 

 be evolved. 



Fire Extinguisher. — Phillips has invented an apparatus 

 (Rep. Pat. Inv. Sept. 1850; Chemist, 1850, and Pharm. Jour. 

 X.) for extinguishing fires by gases incompatible with com- 

 bustion. It consists of an iron cylinder, 2 feet by 8 inches, 

 having at its bottom a shallow chamber filled with water. 

 There is also a smaller cylinder, connecting at the side, and 

 enclosing a brick composed of nitre, charcoal powder, and saw- 

 dust. In the brick is a vial with two compartments, — the 

 upper containing oil of vitriol, and the lower a mixture of 

 chlorate of potassa and sugar. A plug is fitted into the cover 

 of the apparatus in such a position that a sudden blow may 

 cause it to crush the vial and thus ignite the contents. An 

 instantaneous and forcible issue of carbonic acid and oxide, 

 steam and nitrogen follows, and this stream of vapor, directed 

 upon the blazing fire, smothers and extinguishes it. 



Experiments have proved that this arrangement is not ef- 

 fective in open places, where the current of air is very strong. 

 It may, however, be serviceable in confined places, such as the 

 hold of a vessel. 



