410         CONTRIBUTIONS    TO    ECONOMIC   GEOLOGY,    1907,    PART   II. 
TOPOGRAPHY. 
The  district  is  one  of  hilly  topography,  with  very  little  level  land, 
being  made  up  mainly  of  steep-sided,  narrow-topped,  irregular  ridges 
that  rise  to  the  northwest,  culminating-  in  Little  Black  Mountain, 
which  has  an  altitude  of  about  3,500  feet.a  This  ridge  marks  the  State 
boundary  line  between  Kentucky  and  Virginia.  Along  the  southern 
border  of  the  district  Stone  Mountain  extends  as  a  high,  narrow  ridge, 
S3°05' 
63° 
Fig.  7.— Sketch  map  of  the  Pocket  coal  district,  Virginia,  in  the  Little  Black  Mountain  coal  field. 
rising  about  1,200  feet  above  the  river  at  Pennington  Gap.  The  dis- 
trict is  heavily  wooded  and  thinly  populated  except  along  the  narrow 
stream  valleys. 
DRAINAGE. 
The  principal  stream  of  the  district  is  Straight  Creek,  which  rises 
high  on  the  slope  of  Little  Black  Mountain  and,  flowing  southward, 
empties  into  North  Fork  of  Powell  River,  at  the  head  of  Pennington 
aThis  altitude  was  taken  from  a  reconnaissance  topographic  map  which  can  be  regarded  only  as 
approximate. 
