OTHER RESOURCES 55 



vineyards during one season and drift under them 

 for gold at another season." 



Many times the value of the gold output is the 

 petroleum product. The amount and valuation there- 

 of for 1920 are estimated to be 105,000,000 barrels, 

 valued at $194,000,000. This is not only larger than 

 the output of any other state but constitutes 23.8 

 per cent of the total production of the United States. 

 The oil product compensates California for her defi- 

 ciency in coal, of which the supply is small in amount 

 and of poor quality. Aside from general uses of the 

 oil for heating, power in manufacturing, transporta- 

 tion and generation of electricity all of which are 

 of great value in State development the contribu- 

 tion of the oil wells to agriculture is great and varied. 

 California oil has chiefly an asphaltum base which dis- 

 tinguishes it from the oils of the older states. This 

 has proved of large use in highway improvement both 

 as a cover for concrete road-beds and for direct appli- 

 cation to dirt roads ; other petroleum products supply 

 the motive power for irrigation and drainage pump- 

 ing; for the engines of tractors and for farm motors 

 generally, while the ample home supply of gasoline 

 from oil wells is one of the factors which has enabled 

 California to take the lead in the ownership of auto- 

 mobiles which are run with cheap lubricating oils 

 also from petroleum. Thus the petroleum product 

 furnishes what is needed to move with and move 

 upon, most cheaply and efficiently. 



Many important facts and influences could be 

 cited in connection with other mineral products of 



