222 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1940 



Lest we become too pessimistic in response to such unwelcome 

 figures, we should promptly note that substitutes for petroleum are 

 already known. Gasoline, fuel oil, and lubricating oil can now be 

 manufactured from coal and other rocks rich in carbon, by processes 

 of hydrogenation and polymerization. These are expensive processes 

 and their products cannot now compete with the products from pe- 

 troleum even in countries far removed, both geographically and 

 psychologically, from the more productive oil fields.* They will, 

 however, come into use more and more in the next few decades. 



Enougli bituminous and subbituminous coal is known to be avail- 

 able within the United States to meet the present annual demand for 

 coal, plus enough to manufacture gasoline and fuel oil in sufficient 

 quantity to meet current demands for at least 2,000 years. In addi- 

 tion there is enough oil shale — a rock rich in carbon but containing 

 little or no oil — to meet present needs for petroleum products for 

 at least 3,000 or 4,000 years. 



Although petroleum affords an excellent illustration of the rela- 

 tion of nonrenewable resources to the activities of man, it is by no 

 means typical of the items comprising nature's accumulated capital. 

 For nearly all of the important nonrenewable resources, the known 

 w^orld stores are thousands of times as great as the annual world 

 consumption instead of less than a hundred times. But for the few 

 which like petroleum are not known to be available in such vast 

 quantities, the story is much the same. Substitutes are already 

 known, or potential sources of alternative supply are already at 

 hand, in quantities adequate to meet our current needs for at least 

 2,000 or 3,000 years. There is, therefore, no prospect of the immi- 

 nent exhaustion of any of the essential raw materials, so far as 

 the world as a whole is concerned, provided our demands for them 

 are not multiplied rapidly in the future. 



That, of course, raises another question. Will the demand for 

 nonrenewable resources increase materially in the future and thus 

 hasten their exhaustion? Recalling the fact that the human popu- 

 lation of the earth has increased almost fivefold in number in the 

 last 300 years, we might well be fearful on that score. The study 

 of current population trends, however, makes it readily apparent 

 that the next few hundred years will by no means duplicate that 

 record of the past. If present trends continue, the all-time maxi- 

 mum population of the United States will be attained about the 

 year 1970 and will total little more than 150 million souls." There- 



* Heald, K. C, Technology and the mineral industries. WPA National Research Project, 

 Rep. E-1. pp. 27-31, 1937. 



* Thompson and Whelpton, National Resources Committee, Population Statistics, vol. 1, 

 National data, p. 9, 1937. 



