4 SCIENCE REMAKING THE WORLD 



antithesis not yet understood by men. In the World 

 War the airplane dropped bombs within the range over 

 which the airplane could fly. The dirigible balloon 

 could carry heavier bombs over a longer range, but the 

 gas which carried the dirigible aloft was highly inflam- 

 mable, and a gun shot through the gas bag meant con- 

 flagration and a terrible death to those who were in the 

 balloon. But a scientist studying the sun found 

 helium in the sun's chromosphere. Of what use to us 

 would the sun's helium be? Then helium was found 

 in a mineral in the earth. Helium, lighter than air, 

 was not inflammable, was not easily affected by electric 

 currents thus an ideal gas for dirigible balloons. 

 Helium, supposedly very rare, could be secured only 

 at a cost of something like $1,500 per cubic foot, and a 

 large dirigible balloon requires a million or more cubic 

 feet of the gas. Then another scientist discovered that 

 helium may be secured from natural gas and the gas be 

 improved for domestic use when the helium is removed. 

 Later developments will permit men now to secure large 

 quantities of helium at a cost of a few cents per cubic 

 foot. Thus dirigible balloons may be floated on the 

 air by a non-inflammable, non-electrifiable gas at 

 heights and over distances hitherto thought impos- 

 sible. 



During this development, new discoveries regarding 

 explosives have increased their efficiency, so that now 

 it is said that a single ton of the highest explosive will, 

 if advantageously placed, serve to destroy the largest 

 existing battleship. Or if the bomb is loaded with the 

 latest destructive gases, it will snuff out the life of all 



