360  CONTRIBUTIONS    TO    ECONOMIC    GEOLOGY,  1903.  [bull.225. 
Laramie  formation  as  represented  in  central  Wyoming.  The  coal 
measures  occur  within  a  series  about  1,000  feet  thick.  There  are 
seven  workable  beds  in  the  Red  Lodge  mine,  varying  in  widths  from 
5  to  It  feet,  and  comprising  a  total  thickness  of  approximately  54 
feet.  These  different  deposits  are  designated  as  Nos.  1,  2,  3,  4,  4£,  5, 
and  6.  Beginning  at  the  top,  No.  1  has  a  thickness  of  5  feet,  with  a 
2-inch  layer  of  bony  coal  near  the  middle.  It  is  overlain  by  massive 
sandstones  and  underlain  by  so-called  fire  clay.  No.  2  is  7  feet  thick, 
overlain  by  an  impure,  coaly  shale,  varying  in  thickness  from  a  few 
inches  to  2  feet.  No.  3  has  a  total  thickness  of  14  feet,  with  many 
shale  intercalations.  Seam  No.  4  is  8  feet  2  inches  thick  and  contains 
several  small  partings.  No.  4£,  a  horizon  recently  developed  in  the 
Red  Lodge  mine,  has  a  thickness  of  4£  feet  with  one  2-inch  parting  of 
bony  coal.  The  roof  is  composed  of  massive,  gray  sandstone,  the 
floor  of  a  gray,  compact  clay.  Seam  No.  5  has  a  total  thickness  of  11 
feet,  but  contains  numerous  shale  intercalations  which  will  aggregate 
4  feet.  A  2-foot  layer  of  soft,  gray,  sandy  shale  immediately  over- 
lies the  coal,  merging  upward  into  massive,  gray  sandstone.  Bed 
No.  6,  the  lowest  in  the  series,  is  5  feet  thick.  It  has  a  roof  of  hard, 
gray  shale,  varying  in  width  from  6  inches  to  3  feet.  The  product 
of  these  different  beds  shows  some  variation  in  quality.  That  of  Nos. 
2  and  4  is  preferred  as  a  domestic  and  steam  coal,  while  No.  6  is  best 
suited  for  metallurgical  purposes.  In  addition,  13  coal  horizons  are 
reported  to  occur  below,  5  of  which  are  said  to  be  of  workable  char- 
acter. The  coal  measures  outcrop  along  the  east  bluff  of  Rocky 
Fork,  with  a  varying  southerly  dip  of  17°  at  the  Red  Lodge  mine, 
but  this  dip  rapidly  decreases  to  the  southeast  and  south. 
Development  was  first  begun  in  this  district  at  Red  Lodge,  Mont., 
in  1887,  but  the  output  was  small  for  the  two  succeeding  years.  The 
first  shipments  were  made  in  1889,  and  since  that  time  there  has  been 
an  annual  production  of  600,000  tons,  with  a  shipping  value  of  about 
$2  per  ton.  The  product  in  1902  was  over  a  half  million  tons,  valued 
at  $1,200,000.  The  mine  was  formerly  operated  by  the  Rocky  Fork 
Coal  Company,  but  in  1899  was  purchased  by  the  Northwestern 
Improvement  Company.  A  large  portion  of  the  product  is  shipped 
northwest. 
About  4  miles  southeast  of  Red  Lodge,  Mont. ,  at  the  head  of  Bear 
Creek,  several  openings  have  been  made.  This  area  is  localty  known 
as  the  Bear  Creek  coal  district.  The  coal  is  found  in  the  upper  sandy 
division  of  the  Laramie  and  belongs  to  the  same  general  horizon  as  the 
Red  Lodge  mines.  The  dip  of  the  beds  is  4°  southwest.  Five  differ- 
ent beds  have  been  located  at  this  place;  commencing  at  the  top  they 
are  designated  as  Nos.  1,  2,  3,  4,  and  5,  and  are  5i,  6,  8,  4,  and^4  feet 
thick,  respectively.     No.  2  is  the  only  horizon  worked  at  present.     It 
