vi PREFACE 



have entered the lists with the weapons of accuracy and 

 certainty which alone can solve the problem satisfactorily. 

 The history of our subject has not always escaped the 

 stigma of charlatanry and perhaps it has often deserved 

 it. With the growing application of established scientific 

 principles and the subsequent checking and verification 

 of these by other boreholes, shafts, etc., we may regard 

 the day of skepticism as vanished. There is now arising 

 an insistent and ever increasing desire for frankness, 

 clarity and truth in borehole investigation which must one 

 day achieve the universal respect accorded an exact 

 science. Built on such foundations it is indeed difficult 

 to imagine this ideal failing. 



M. H. Haddock. 



Leicester, England, 

 Septe77iber, 1931, 



