468 JOSEPH BARRELL 



determining the depth of the outstanding masses assumed as spheres, 

 provided the section Hne is not farther from the epicenter than the 

 latter is above the center of mass. The method may be used, 

 however, with less precision for distances of the traverse hne E'E 

 up to 2D. Beyond this distance, however, influences of other 

 masses or errors in the geodetic data would be likely to give wholly 

 erroneous results, not distinguishing between a large excess of mass 

 at a great depth or a smaller one at a much less depth. 



{To be continued} 



