214 FIRE PREVENTION IN THE HOME 



of chemical extinguishers suitable for use in the house, 

 the school, and the shop when the fire is small. 



Experiment. How to extinguish (a) burning fat; (b) burning gasoline. 



Materials: Lard. Gasoline. Evaporating dish. Ring stand. Heavy 



cloth. Carbon tetrachloride. Test tubes. 



Method and Results : (a) Heat a teaspoonf ul of lard in an evaporating dish. 

 When smoking hot let two or three drops of water fall into it. Would 

 water be a good substance to extinguish burning fat? Wet the cloth 

 and carefully lay it over a dish of burning fat, excluding all air. 



(&) Pour a tablespoonful of gasoline into the small evaporating dish. 

 Set it on fire. Pour water from the test tube into it. Is the fire 

 extinguished? Smother with a cloth. Pour this out and use another 

 tablespoonful of gasoline. Set it on fire. Pour carbon tetrachloride 

 into it from a test tube. Result? 



(N.ote: Carbon tetrachloride is non-inflammable and evaporates as 

 easily as gasoline.) 



Conclusion: What advice would you give for extinguishing burning fats 

 and gasoline ? 



The carbon tetrachloride extinguisher holds about a pint 

 of volatile liquid in a small container to which a force 

 pump is attached. When the container is opened and the 

 pump worked, a stream of liquid may be thrown upon a 

 near-by blaze. The liquid changes to gas, which smothers 

 the flame. When this extinguisher is used take care not 

 to breath the fumes given off for they are harmful and in 

 a number of instances have proved fatal. This type 

 of extinguisher is particularly valuable for extinguishing 

 small gasoline and oil fires. Water cannot be used for 

 these fires since the oil or gasoline would rise to the surface 

 of the water and continue to burn. 



The small carbon dioxide extinguisher holds 2\ gallons 

 of water, in which are dissolved i^ pounds of baking soda 

 and a bottle containing 4 oz. of strong sulphuric acid is 

 suspended above the solution. When the extinguisher 



