SAFETY MATCHES 47 



of oxygen needed for the fires of the world comes largely from 

 the atmosphere. 



37. Matches. The burning material is ordinarily set on 

 fire by matches, thin strips of wood tipped with sulphur or 

 phosphorus, or both. Phosphorus can unite with oxygen, at 

 a fairly low temperature, and if phosphorus is rubbed 

 against a rough surface, the friction produced will raise the 

 temperature of the phosphorus to a point where it can com- 

 bine with oxygen. The burning phosphorus kindles the wood 

 of the match, and from the burning match the fire is kindled. 

 If you want to convince yourself that friction produces heat, 

 rub a cent vigorously against your coat and note that the 

 cent becomes warm. Matches have been in use less than a 

 hundred years. Primitive man kindled his camp fire by 

 rubbing pieces of dry wood together until they took fire, 

 and this method is said to be used among some isolated 

 distant tribes at the present time. A later and easier 

 way was to strike flint and steel together and to catch the 

 spark thus produced on tinder or dry fungus. Within the 

 memory of some persons now living, the tinder box was a 

 valuable asset to the home, particularly in the pioneer 

 regions of the. West. 



38. Safety Matches. Ordinary phosphorus, while excel- 

 lent as a fire-producing material, is dangerously poisonous, 

 and those to whom the dipping of wooden strips into phos- 

 phorus is a daily occupation suffer with a terrible disease 

 which usually attacks the teeth and bones of the jaw. The 

 teeth rot and fall out, abscesses form, and bones and flesh 

 begin to decay ; the only way to prevent the spread of the 

 disease is to remove the affected bone, and in some instances 

 it has been necessary to remove the entire jaw. Then, too, 

 matches made of yellow or white phosphorus ignite easily, 

 and, when rubbed against any rough surface, are apt to take 



