S 8 SCIENCE REMAKING THE WORLD 



use made of high explosives; that is, compounds that 

 can be kept and carried with comparative safety but 

 which explode with terrific violence on being set off by a 

 percussion cap of the right sort. The Germans with 

 the chemical factories and nitrate plants were better 

 prepared with these new weapons of warfare and that is 

 why they burst through the border with such alarming 

 speed. The steel and concrete cupolas of the Belgian 

 and French fortresses were shattered to pieces by single 

 shells from the 42 centimetre guns. The British trooptf 

 had to fall back rapidly before Von Kluck's army and 

 even then narrowly escaped destruction. Lord Kitch- 

 ener and the British general staff were slow to realize 

 that the old means of defence and offence were useless 

 against the coal-tar munitions, but finally word was got 

 to the British people that the army in France must 

 have high explosives or perish. They got them in 

 time to make a stand after the first German drive had 

 spent its initial force and so coal-tar products "won the 



war." 



In considering coal-tar explosives we must not think 

 that their usefulness is confined to settling the relative 

 strength of nations in war. Explosives are simply com- 

 pact packages of potential chemical energy put up in a 

 form ready for quick release, and as such they are 

 valuable in various ways. In 1921 the United States 

 produced and used for industrial purposes 538,000,000 

 pounds of explosives. This does not include exports, 

 but includes explosives not made from coal-tar, such as 

 gunpowder and nitroglycerin. 



Carbolic acid, which the chemist calls "phenol," 



