The Romance of Modern Chemistry

HOW FIRE IS MADE waxy solid, very poisonous and very easily inflamed; at other times it is a red powder, not poisonous, and much less readily ignited. Regarded superficially, these two substance* are absolutely different, but they are really the same element in different garb, and chemists have found a way of changing yellow phosphorus into red, or red into yellow. This matter has already been discussed at length in Chapter V. Soon after red phosphorus was discovered, it was sug- gested that the disadvantages of using the ordinary yellow phosphorus in matches might be avoided by substituting the red form, on account of its being non-poisonous and less readily inflamed. Attempts were accordingly made to tip matches with mixtures containing red phosphorus, but these were not very successful. A certain Swede, however, ultimately proposed that, instead of putting the red phosphorus at the end of the match, it might be put on the surface on which the match was to be rubbed. This idea was worked out with complete success, and has led to what are now known as “ safety matches.” These matches will not ignite with ordinary friction on a rough surface; they will strike only on the prepared surface on the box, consisting very generally of red phosphorus, gum, and powdered glass. In order still further to diminish risk of fire, the stems of safety matches are frequently soaked in some chemical, such as alum or magnesium sulphate, so that when the burning match is blown out the wood immediately ceases to glow. A splint of ordinary dry wood, on the other hand, will con- tinue to glow for a little after it has ceased to burn. This the reader can easily verify for himself. The number of matches manufactured nowadays is enormous. It is estimated that in England alone, 300 124