MAN'S SYNTHETIC FUTURE — ADAMS 221 



years, but allowing for difficulties of recovery and for increased de- 

 mand it would appear conservative to estimate they will last for at 

 least 200 to 300 years. I am willing to prophesy that when the time 

 of exhaustion arrives scientists will have found substitutes. 



Petroleum, originally a source merely of kerosene, then of gasoline 

 and lubricating oil, has become, along with natural gas, the raw ma- 

 terial for a host of aliphatic and aromatic chemicals upon which many 

 of our chemical industries are founded. The magnitude can be real- 

 ized best by citing that 1.25 billion pounds of butadiene, obtained by an 

 appropriate cracking process from petroleum, are used annually for 

 825,000 tons of synthetic rubber. From 3i/ 2 billion pounds of ethy- 

 lene, propylene, butylene, and isobutylene, 16 billion pounds of deriv- 

 atives are made each year. Just a decade or two ago the chemical 

 industry relied upon coal tar, the volatile liquids obtained when coal 

 is coked, for many of its raw materials. But with increased use of 

 petroleum for power, and of natural gas for heating, less coal is being 

 coked and the supply of chemicals from the coal tar is much smaller 

 than the demand. Industry has now turned to petroleum for a sub- 

 stantial proportion of its chemicals for the synthesis of dyes, drugs, 

 plastics, and fibers. 



Rapid mechanization has made search for substances to produce 

 energy as well as heat one of our prime objectives. A hundred 

 years ago, it was wood, and now fossil fuels have the attention of 

 a multitude of technologists. It is difficult to conceive of modern 

 life without power and heat. In spite of the discovery from year 

 to year of more reserves of energy-containing materials, the time 

 before these are exhausted is at most a matter of a few hundred years 

 and then a new source of energy must be available. 



A perpetual supply of energy comes from the sun. How vast it 

 is compared to the energy-supplying materials on earth may be 

 realized by a comparison presented in an article by Eugene Ayres. 

 Suppose that all the coal, lignite, peat, tar sands, crude petroleum, 

 natural gas, and oil shale that we are likely to produce in the future 

 on the basis of the most optimistic estimates were collected. Suppose 

 that all the timber of the world were cut into cordwood. Moreover, 

 suppose that all the uranium and thorium that are likely ever to be 

 discovered were purified and made ready for nuclear fission. Sup- 

 pose now that this fuel were distributed over the face of the earth, 

 that the sun were suddenly extinguished, and that the fuel were 

 ignited to give energy at the rate at which we are accustomed to 

 receive it from the sun — the combustible fuel would be gone in three 

 days. Nuclear reactions would last a few hours. The energy that 

 actually reaches the earth from the sun is over 30,000 times that 

 of all the fuel and water power now used. There is absolutely nothing 



