210        CONTRIBUTIONS    TO    ECONOMIC   GEOLOGY,   1907,   PART  II. 
West  Wiley  mine. — The  West  Wiley  mine  is  located  southwest  of 
the  Oregon  Basin,  at  the  base  of  Frost  Ridge,  in  the  SE.  \  sec.  34, 
T.  51  N.,  R.  101  W.  It  consists  of  a  slope  195  feet  long,  with  two 
small  rooms  at  the  bottom.  At  this  mine  the  beds  dip  28°.  The 
coal  occurs  in  two  benches  separated  by  a  layer  of  carbonaceous  shale. 
In  the  east  room  the  lower  bench  is  38  inches  thick  and  the  upper 
bench  6  inches.  In  the  west  room,  however,  the  thickness  of  the 
lower  bench  is  not  so  great.  Section  No.  11,  PL  XI,  is  representative 
of  the  best  conditions  in  this  mine.  The  mine  is  located  near  the 
western  edge  of  a  lenticular  bed.  The  bed  contains  S  feet  of  coal 
where  it  is  exposed  in  a  ravine  one-eighth  of  a  mile  to  the  east,  an;1. 
a  short  distance  farther  east  it  passes  below  workable  limits.  To  the 
west  the  beds  are  variable  and  probably  workable  at  several  pom  Is 
between  the  mine  and  Sage  Creek. 
•  The  mine  is  operated  chiefly  to  supply  coal  to  the  Bighorn  Basin 
Development  Company,  which  is  constructing  extensive  irrigation 
works  in  the  vicinity.  A  small  part  of  the  coal  is  sold  for  domestic 
purposes  at  $3  per  ton.  The  annual  production  is  about  150  tons. 
The  coal  has  a  brownish-black  color,  pitchy  luster,  and  moderately 
smooth  joints  where  not  affected  by  slickensiding.  It  has  been 
badly  crushed,  however,  by  the  uplift  of  the  beds,  and  as  a  conse- 
quence breaks  irregularly  and  yields  a  high  percentage  of  fine  coal  in 
mining. 
Orr's  mine. — Orr's  mine  is  on  the  west  limb  of  a  syncline  lying 
between  the  Oregon  Basin  and  Sage  Creek,  in  the  NW.  \  sec.  12,  T. 
50  N.,  R.  102  W.  It  is  near  the  crest  of  a  hogback  of  Eagle  sand- 
stone that  dips  47°.  A  drift  has  been  driven  for  125  feet  along  the 
strike  and  a  small  amount  of  coal  taken  out,  mostly  from  an  open 
pit  which  has  not  reached  below  the  zone  of  weathering.  A  section 
of  the  coal  bed  is  shown  in  No.  13,  PL  XL  The  large  number  of 
partings  and  the  steep  dip  of  the  strata  preclude  extensive  develop- 
ment at  this  mine. 
Prospecting. — Some  prospecting  has  been  done  in  the  northern  part 
of  the  Cody  field  near  Heart  Peak  and  at  several  places  northeast  of 
Cody.  The  part  of  the  district  lying  north  of  Shoshone  River  seems  to 
contain  very  little  workable  coal,  and  even  where  the  coal  beds  are  of 
sufficient  thickness  to  be  minable  the  steep  dip  of  the  strata  prevents 
extensive  development. 
South  of  the  river  prospecting  has  been  done  at  various  places, 
notably  east  of  the  Oregon  Basin  and  along  Frost  Ridge.  At  the 
former  locality  the  coal  appears  to  have  a  sufficient  thickness  and 
favorable  attitude  for  the  opening  of  small  mines.  On  the  north  side 
of  Frost  Ridge  also  there  are  several  promising  locations.  The  bed 
mentioned  as  exposed  in  a  gulch  south  of  the  West  Wiley  mine, 
