302 
CONTRIBUTIONS    TO    ECONOMIC    GEOLOGY,  1903.  [bull. 225. 
Following  is  a  comparison  of  the  average  of  10  determinations  of 
coal  from  the  Greenwich  mines  and  an  average  analysis  of  the  Con- 
nellsville coal  furnished  by  the  H.  C.  Frick  Coke  Company. 
Comparative  analyses  of  Connellsville  and  Lower  Freeport  coals. 
Moisture - 
Volatile  combustible  matter 
Fixed  carbon 
Ash 
Sulphur 
Phosphorus 
Connellsville 
coal,H.C 
Frick  Coke  Co. 
100.  000 
Lower  Free- 
port  coal, 
Greenwich 
Per  cent. 
Per  cent. 
1.130 
(a) 
29.  812 
25. 099 
60.  420 
66.  300 
7.949 
7.757 
.689 
.840 
(a) 
.004 
100.  000 
a  Not  determined. 
No  moisture  determinations  were  made  of  the  Lower  Freeport  coal 
in  these  analyses,  but  a  number  of  others  show  the  moisture  to  be 
much  less  than  1  per  cent. 
The  approximate  ratio  of  volatile  hydrocarbons  to  fixed  carbon  of 
both  coals  is,  Connellsville  1:2;  Lower  Freeport  5:13;  that  is,  the 
Connellsville  coal  contains  about  twice  as  much  fixed  carbon  as  volatile 
hydrocarbons  and  the  Lower  Freeport  between  two  and  three  times  as 
much.  This  is  the  only  locality  in  the  field  from  which  coal  has  been 
taken  for  the  manufacture  of  metallurgical  coke  in  by-product  ovens. 
As  previously  mentioned  the  quality  of  the  coal  appears  to  improve 
near  the  western  margin  of  the  field  as  at  present  determined. 
Recently  a  private  analysis  of  a  drill  core  from  a  point  still  farther 
west  is  reported  as  showing  a  much  smaller  percentage  of  ash  and  a 
ratio  of  volatile  hydrocarbons  to  fixed  carbon  equal  to  that  of  the 
Connellsville  coal. 
MINES. 
There  are  about  40  mines  in  this  field  working  the  Lower  Freeport 
coal  on  a  commercial  scale,  and  as  they  all  employ  similar  methods  and 
equipment  a  description  of  the  several  centers  of  activity  will  suffice. 
At  Hastings  the  largest  mine  as  well  as  the  oldest  in  the  field,  hav- 
ing been  operated  since  1887,  is  Pennsylvania  No.  20,  formerly  Ster- 
ling No.  8,  operated  by  the  Pennsylvania  Coal  and  Coke  Company. 
The  main  heading  of  this  mine  extends  down  the  dip  for  more  than  2 
miles,  and  haulage  for  nearly  its  entire  length  is  by  rope.  Mules 
gather  the  cars  from  the  headings,  and  with  this  system  one  of  the 
largest  daily  outputs  of  the  field  is  maintained.     The  coal  is  undercut 
