60  CONTRIBUTIONS    TO    ECONOMIC    GEOLOGY,   1907,   PART   II. 
No  samples  of  Miles  City  coal  have  been  tested  under  boilers  or 
with  the  gas  engine  by  the  United  States  Geological  Survey,  but  such 
tests  of  two  samples  from  the  Bridger  bed  in  the  Red  Lodge  field, 
with  which  these  coals  are  compared  by  Miles  City  engineers,  are 
described  on  pages  174  to  177  of  Survey  Bulletin  No.  332,  and  a  gas- 
producer  test  of  lignite  from  Williston,  N.  Dak.,  which  resembles  that 
from  the  upper  member  near  Miles  City,  is  described  in  Bulletin 
No.  261,  page  105.  These  tests  indicate  that  with  the  Bridger  coal 
5.04  pounds  as  fired  are  consumed  per  electric  horsepower  hour  under 
boilers  and  1.80  to  2.34  pounds  by  the  gas  producer  and  gas  engine. 
With  the  Williston  lignite  3.67  pounds  as  fired  are  consumed  per 
electric  horsepower  hour  by  the  gas  producer. 
DEVELOPMENT. 
One  of  the  first  attempts  to  develop  the  coals  of  this  field  was  made 
by  the  Northern  Pacific  Company  soon  after  the  completion  of  the 
railroad,  the  point  selected  being  near  the  edge  of  the  right  of  way  at 
the  head  of  Keogh  Flat,  6  or  7  miles  above  Miles  City,  where  the 
company  located  a  small  mining  village  called  Lignite.  Operations 
here  have  been  suspended  for  several  years,  the  buildings  having  been 
moved  away  and  the  openings  abandoned.  The  coal  obtained  was 
not  suitable  for  use  in  locomotives. 
At  about  the  same  time  the  Comstock  mine,  north  of  Yellowstone 
River,  opposite  Miles  City,  was  opened  and  has  been  operated  unsys- 
tematically  from  year  to  year.  None  of  the  development  has  been 
of  a  permanent  character  and  most  of  the  old  drifts  have  caved  in, 
though  it  is  probable  that  several  thousand  tons  of  coal  have  been 
mined  here  and  hauled  to  Miles  City  by  a  roundabout  road  crossing 
the  river  2  miles  above. 
The  many  old  openings  on  coal  beds  near  Signal  Butte  indicate 
rather  extensive  but  unsystematic  mining  there  for  many  years, 
though  in  the  summer  of  1907  all  the  openings  seemed  to  be  aban- 
doned. Similar  conditions  are  to  be  observed  on  the  left  bank  of 
Tongue  River,  5  miles  above  town.  In  addition  to  these  localities 
there  are  many  country  banks  scattered  over  the  field  from  which 
ranchmen  obtain  fuel  for  domestic  use,  the  prevalent  methods  of 
mining  such  deposits  being  either  by  stripping  or  by  undermining  the 
coal  in  the  cut  banks  of  streams. 
The  Kircher  mine,  6  miles  northeast  of  Miles  City,  is  on  a  somewhat 
more  extensive  scale.  The  coal  bed  here  is  63  feet  below  the  surface 
and  is  reached  by  a  slope.  The  mine  is  worked  by  the  room  and 
pillar  system,  the  mining  being  done  by  shooting  off  the  solid  with 
small  charges  of  powder.  Mine  cars  are  pushed  by  hand  to  the  foot 
of  the  slope,  up  which  they  are  drawn  by  cable  from  a  horse  whim. 
Ventilation  is  accomplished  by  a  fire  box  and  mine  water  is  pumped 
