436 MAGNETIC METHOD [Chap. 8 



changed the construction plp-ns and made it possible to use basalt pillars 

 as foundations for a power house. 



4. If the location of buried metal (pipe lines, ammunition) is known 

 approximately, it may be readily found by magnetometers adaptable to 

 rapid surveys, such as the dip needle and similar magnetometers. A 

 Keuffel and Esser prospectus describes the location of two pipe lines, and 

 an article by Ebert"^ discusses the location of a buried ammunition 

 magazine by electrical and magnetic measurements (see Fig. 8-77) . Verti- 

 cal intensity anomalies up to 4OO7 were observed. Two lost magazines 

 were found by combined electrical and magnetic measurements. 



»" Beitr. angew. Geophys., 1(1), 9-14 (1930). 



