56 



ILLINOIS ACADEMY OF SCIENCE. 



in 2^ years if the production continued to increase at the same 

 rate. It is interesting to notice that during the past three years 

 the rate has been more than maintained, as shown by the illus- 

 tration. Each field of the country reaches a maximum produc- 

 tion and declines more or less rapidly. The Pennsylvania-New 

 York field has declined in seventeen years to one-third of its 

 maximum yield. West Virginia production has already declined 

 to 56 per cent of its greatest output. Unless new fields are fre- 

 quently discovered, an inevitable decline in total production is 

 imminent. 



Wastes of Petroleum. 



In view of the irreparable loss of petroleum which follows its 

 extraction, it is desirable to reduce as completely as possible the 

 losses in production and utilization. The principal losses in 

 extraction are indirectly caused by the fact that oil is mobile and 

 that each owner in a given field is obliged to get his share as 

 quickly as possible. Thus, facilities are not always provided for 

 controlling the flow of new wells and of gushers. Frequently, 

 no adequate storage tanks are provided and the oil lies for weeks 

 in great earthen reservoirs, and is exposed to evaporation. These 

 losses are indeed serious, but are subject to correction. A third 



Plate II. 



Darrels. 



P. 10,000 fiOO 



?<»,000,000 

 190,000,000 

 l«0,OOOflOO 



i7o.ooc.noo 



160.000.000 

 150,000.000 

 140,000.1100 

 130,000,000 

 120.000,000 

 110,000.000 

 100,000,000 

 90.000.000 

 80,000,00(1 

 70,000,000 

 60,000,000 

 50.000.000 

 40,000.000 

 30.000,000 

 20,000,000 

 10.000,000 



ow2£Sma6S««toooaoobwCicmmaowSao2Sx5Soooooo cjoccoocoooooco 00 ota-. a>9>a»ai&ta>» < 



PRODUCTION OF PETROLEUM, 1859 TO 1910 . 



