THE  WESTERN  PART  OF  THE  LITTLE  SNAKE  RIVER 
COAL  FIELD,  WYOMING. 
By  Max  W.  Ball. 
INTRODUCTION. 
This  paper  is  a  brief  statement  of  the  results  of  a  survey  made 
in  1907  by  the  writer,  assisted  by  B.  L.  Johnson,  J.  T.  Singewald,  jr., 
L.  Reinecke,  Robert  D.  Sawin,  and  for  a  month  early  in  the  season 
by  V.  H.  Barnett.  Geologic  and  topographic  mapping  was  done  on 
a  scale  of  2  inches  to  the  mile.  Locations  were  determined  by 
pacing  from  land-subdivision  corners;  elevations  were  based  on 
aneroid-barometer  readings,  controlled  by  a  line  of  levels  run  diag- 
onally across  the  field  from  Rawlins  to  Baggs. 
The  map  (PL  XIII)  accompanying  tins  paper  has  been  compiled 
from  the  field  sheets  to  show  only  the  more  prominent  cultural  and 
drainage  features  and  the  main  geologic  facts  related  to  the  occur- 
rence of  coal.  The  boundaries  of  the  coal-bearing  formations  are 
indicated,  but  no  attempt  is  made  on  this  map  to  show  the  location 
of  actual  coal  outcrops.  With  the  exception  of  a  few  corner  stones 
near  Five  Buttes  and  a  few  stones  that  were  established  along 
Muddy  Creek  by  E.  Lambert,  county- surveyor,  no  land  corners 
were  ever  set  in  Tps.  14,  15,  and  16  N.,  in  this  field,  and  the 
location  on  the  map  of  the  features  in  this  part  of  the  field  can 
not  be  considered  accurate.  In  preparing  the  present  base  map 
the  lengths  of  the  land  lines  as  given  on  the  plats  of  the  original 
Land  Office  surveys  were  accepted  as  correct  and  were  plotted  by 
so  balancing  the  recorded  distances  about  vertical  and  horizontal 
right  lines  intersecting  near  the  center  of  the  map  that  the  distor- 
tions due  to  convergence  of  meridians  and  errors  of  surveying  were 
distributed  equally  over  the  sheet.  As  a  result  of  this  balanced 
plotting  of  distances  rather  than  directions  the  length  of  the  sides 
of  any  given  township  or  section  is  the  same  as  that  shown  on  the 
Land  Office  plat,  but  the  shape  of  the  township  or  section  may  be 
different  from  the  shape  given  on  that  plat  or  from  the  shape  which 
would  be  obtained  if  the  balance  lines  were  located  in  some  other 
position.     Thus  this  map  does  not  exactly  agree  with  the  map  of 
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