22  CONTRIBUTIONS    TO    ECONOMIC    GEOLOGY,  1905. 
FUELS  AND   OTHER   HYDROCARBONS. 
The  great  activity  in  the  investgation  of  the  fuel  resources  of  the  country  which  was 
noted  in  "Contributions  to  Economic  Geology"  for  1904  was  continued  and  considerably 
extended  during  the  season  of  1905.  This  extension  was  due  in  large  measure  to  the  gen- 
eral interest  which  was  taken  in  the  investigations  carried  on  by  the  fuel-testing  division 
and  to  a  large  amount  of  geologic  work  in  the  coal  fields  of  the  country,  which  was  made 
possible  by  an  increase  in  appropriations. 
Coal. — To  coordinate  the  geologic  work  in  various  parts  of  the  country,  Mr.  M.  R.  Camp- 
bell was  directed  to  exercise  supervision  over  the  investigations  of  coal  resources  through- 
out the  United  States.  Although  Mr.  Campbell's  work  was  to  include  the  entire  country,  it 
was  understood  thai  he  was  to  give  particular  at  tent  ion  to  the  Rocky  Mountain  region,  and 
that  in  connection  with  the  regular  geologic  work  he  was  to  cooperate  with  the  coal-testing 
plant  at  St.  Louis  1>\  securing  samples  of  coal  to  be  tested. 
In  the  Appalachian  region  geologic  work  was  carried  on  at  three  localities — western 
Pennsylvania,  eastern  Kentucky,  and  central  Alabama.  In  Pennsylvania  about  750  square 
miles  of  coal  territory  was  surveyed  in  great  detail.  In  eastern  Kentucky  an  area  of  about 
950  square  miles  was  thoroughly  examined;  and  in  Alabama  a  part  of  the  coal  field,  about 
500  square  miles  in  extent  near  the  city  of  Birmingham,  was  also  examined  with  great  care. 
In  the  Rocky  Mountain  region  a  number  of  coal  fields  have  been  attracting  the  attention 
of  coal  operators  and  railroad  men  for  some  time.  Reconnaissance  surveys  were  made 
over  several  of  these  fields  in  order  to  provide  the  public  with  information  in  advance  of 
active  development  in  railroad  construction.  A  large  part  of  the  Durango-Gallup  field  in 
southern  Colorado  and  northwestern  New  Mexico,  covering  an  area  of  about  2,000  square 
miles,  was  studied,  and  the  various  coal  groups  were  mapped.  Similar  work,  though  perhaps 
in  greater  detail,  was  done  over  the  larger  part  of  the  Yampa  coal  field  of  Routt  County, 
northwestern  Colorado.  Great  activity  has  been  manifested  in  this  field  lately  through 
the  prospective  building  of  the  Denver,  Northwestern  and  Pacific  Railway  through  this 
field.  The  coals  generally  are  of  the  bituminous  variety,  but  in  the  northern  part  of  the 
field  there  is  a  small  area  in  which  the  coal  has  been  converted  to  anthracite.  This  is  due 
to  local  metamorphism,  and  the  field  is  consequently  of  limited  extent. 
In  Utah  an  attempt  was  made  to  examine  the  entire  coal-bearing  areas  of  the  State  in 
cooperation  with  the  General  Land  Office.  The  shortness  of  the  season  permitted  an 
examination  only  of  the  Book  Cliffs  area  from  the  Sunnyside  mine  westward  and  also  of  the 
small  coal  field  in  the  vicinity  of  Coalville.  The  Book  Cliffs  field  is  of  great  importance, 
and  the  maps  and  report  prepared  during  this  survey  will  doubtless  be  of  great  value.  In 
addition  to  the  regular  systematic  work  on  the  Book  Cliffs  field  some  information  was  also 
obtained  regarding  coals  in  San  Pete  County.  These  are  small  outlying  areas,  and  prob- 
ably never  will  be  of  great  value  except  for  local  use. 
In  Wyoming  special  attention  was  given  to  the  coal  fields  of  the  southwestern  part  of 
the  State  in  what  is  generally  known  as  the  Hams  Fork  coal  field.  This  was  examined 
with  great  care,  with  the  object  of  determining  both  the  fuel  value  and  geographic  distri- 
bution of  the  coals,  as  well  as  the  amount  of  unclaimed  coal  land  still  remaining  in  the 
field.  Incidentally  considerable  data  were  obtained  regarding  the  coal  field  of  the  Bighorn 
basin,  but  this  was  done  in  connection  with  the  investigation  of  underground  water,  and 
consequently  was  not  of  so  detailed  a  character  as  the  work  just  mentioned. 
In  North  Dakota  and  Montana  the  work  already  begun  by  the  North  Dakota  Geological 
Survey  was  extended  so  as  to  cover  the  valley  of  Little  Missouri  River  south  of  the  North- 
ern Pacific  Railway  and  the  territory  west  into  Montana.  In  the  latter  State  reconnaissance 
work  was  carried  on  from  the  mouth  of  Yellowstone  River  as  far  up  as  Miles  City.  Here- 
tofore the  brown  lignites  of  this  region  have  not  been  regarded  as  particularly  valuable  for 
fuel  purposes,  but  the  tests  made  at  the  Government  coal-testing  plant  on  brown  lignites 
as  a  fuel  for  the  manufacture  of  producer  gas  show  such  excellent  results  that  it  seems  pos- 
