412         CONTRIBUTIONS   TO    ECONOMIC   GEOLOGY,   1007,   PART   II. 
the  relative  positions  of  the  various  workable  coal  beds  of  this  district, 
is  given  below: 
Generalized  section  showing  positions  of  coal  beds  in  the  Pocket  district,  Virginia. 
Feet. 
Harlan  sandstone  (?) ,  exposed 40 
Coal  bed  12 A\ 
Interval GO 
Coal  bed  11 3 
Interval 300 
Coal  bed  10 6 
Interval 40 
Coal  bed  9 4£ 
Interval 100 
Coal  bed  8 4 
Interval 100 
Coal,  impure 4 
Interval 100 
Coal  bed  7 3£ 
Interval 325 
Coal  bed  6 A\ 
Interval 275 
Coal  bed  5 3£ 
Interval 180 
Coal  bed  4 2\ 
Interval 180 
Coal  bed  3 3* 
Interval 40 
Coal  bed  2  A 3 
Interval 40 
Coal  bed  2 3 
Interval 300 
Coal  bed  1 4£ 
2,134 
DETAILED  DESCRIPTION  OF  COAL  BEDS. 
General  statement. — Only  the  coal  beds  of  commercial  importance 
occurring  in  the  upper  half  of  the  Pottsville  group  were  studied.  A 
number  of  coal  beds  lower  in  the  Pottsville,  and  also  in  the  basal  for- 
mation of  that  group,  the  Lee  conglomerate,  have  been  mined  at 
country  banks  for  years,  but  these  are  thin  and  they  were  not  exam- 
ined. According  to  reports,  there  are  five  or  six  of  these  beds,  ran- 
ging in  thickness  from  2  to  3  feet. 
The  following  notes  give  in  ascending  order  a  brief  description  of 
the  stratigraphic  position,  thickness,  and  general  characteristics  of 
each  of  the  more  important  workable  coal  beds  in  the  Pocket  coal 
district. 
Bed  1. — About  2,090  feet  below  the  base  of  what  is  believed  to  be 
the  Harlan  sandstone  occurs  a  coal  bed  which  is  known  locally  as 
