A map can be contoured so that all of the technical requirements just de- 

 scribed are fully satisfied, yet fail to convey the probable structural conditions. 

 Such a map is shown in A of Figure 24-12. There are no technical errors in the 

 contouring of this map, but it fails to give a consistent picture of structure. On 



Figure 24-12. Contrast of careless and orderly methods of contouring the same data. 



465 



