LOCATION AND MOVEMENTS OF UNDERGROUND WATERS 49 



and often unconscious tightening of grip on the rod always sent 

 the tip downward at once, and the tighter one held the more it 

 bent. 



It was soon shown, however, that there were no movements of 

 the rod arising from causes outside of the body and it was obvious 

 that the view held by other men of science is correct that the 

 operation of the " divining rod " is generally due to unconscious 

 movements of the body or of the muscles of the hand. The ex- 

 periments made show that these movements, being largely of a 

 nervous nature, happen most frequently at places where the 

 operator's experience has led him to believe that water may be 

 found. 



The uselessness of the divining rod is indicated by the fact 

 that it may be worked at will by the operator, that he fails to de- 

 tect strong water currents in channels that afford no surface in- 

 dications of water, that his locations in limestone regions where 

 water flows in well-defined channels under conditions that should 

 be especially favorable to the working of the rod are usually no 

 better than mere guesses, and that two " divining rod experts " 

 going over the same tract commonly locate the supposed under- 

 ground "streams" at entirely different points. 



In fact, the operators of the divining rod are successful only in 

 regions in which ground water occurs in a definite sheet in porous 

 material or in more or less clayey deposits, such as pebbly clay 

 or till. In such regions few failures can occur, for wells can get 

 water almost anywhere. Ground water occurs under certain 

 definite conditions, and just as surface streams may be expected 

 wherever there is a valley, so ground water may be found where 

 certain rocks and conditions exist. No appliance, either me- 

 chanical or electrical, has yet been devised that will detect water 

 in places where plain common sense will not show its presence 

 just as well. The only advantage of employing a " water witch," 

 as the operator of the divining rod is sometimes called, is that 

 crudely skilled services are thus occasionally obtained, since the 

 men so employed, if endowed with any natural shrewdness, 



