276 Microbes and You 



utilizing organism, flasks of such cultures can be lowered into 

 wells suspected of containing oil-bearing deposits. If petroleum 

 vapors are present in the wells, the organisms will utilize the car- 

 bon in these vapors and the test culture will grow. So the bac- 

 teriologist joins hands with the geologist and with other scientists 

 in this fascinating detective work for the petroleum industry. 



