burrows]       BARNESBOKOPATTON  COAL  FIELD,   PENNSYLVANIA.        301 
Section  of  Lower  Freeport  coal  near  disturbed  zone  at  Barnesboro 
Sandstone  roof. 
Bone 
Slate 
Coal 
Binder 
Coal 
Limestone. 
Total 5 
Ft. 
in. 
0 
8 
0 
6 
3 
4 
0 
2 
0 
8 
Shale  roof. 
Coal 
Binder  . . . 
Coal 
Fire-clay  floor. 
Total . . . 
Section  of  Lower  Freeport  coal  at  Carrolltown. 
Ft. 
In. 
3 
0 
0 
2 
0 
10 
Clay  veins  are  a  great  -source  of  trouble  in  this  bed,  and  in  places 
they  are  so  large  as  to  make  the  working  of  the  coal  unprofitable. 
The  majority,  however,  are  not  more  than  11  to  20  inches  in  thickness 
and  are  cut  through  in  the  regular  course  of  the  work.  Scarcely  a 
mine  in  the  entire  field  is  free  from  them.  Besides  clay  veins,  some 
of  the  mines  are  greatly  troubled  with  "  roof  rolls"  (unconformity  of 
roof  and  coal),  and  along  the  west  branch  of  Susquehanna  River, 
between  Barnesboro  and  a  point  south  of  Spangler,  there  exists  a  zone 
of  disturbance  that  appears  to  be  caused  b}^  a  fold  running  about 
S.  20°  E.  This  disturbance  is  accompanied  by  local  thinning  and 
crushing  of  the  coal,  which  has  given  considerable  trouble  in  the  West 
Branch,  Susquehanna  No.  1,  and  Gussie  mines.  Disturbance  in  the 
intervening  area  is  plainly  shown  b/y  diamond  drill  records,  but  its 
extent  is  not  accurately  known. 
Quality  of  the  coal. — The  Lower  Freeport  coal  carries  a  large 
amount  of  sulphur  in  the  form  of  "knife  blades"  and  iron  nodules  in 
many  parts  of  the  region.  Impurities  seem  to  decrease  west  of 
Barnesboro  and  the  coal  becomes  suitable  for  coking.  The  coal  of  the 
Greenwich  mines  near  Garmans  Mills  is  shipped  to  the  Maryland 
Steel  Company  at  Sparrows  Point,  Md.,  where  it  is  coked  in  by-product 
ovens  with  excellent  results.  Three  reported  analyses  of  the  coal 
from  these  mines  show  the  following  composition : 
Analyses  of  the  L,ower  Freeport  coal  from  near  Garmans  M 'ills,  F<i. 
Moisture 
Volatile  combustible  matter . 
Fixed  carbon 
Ash 
Sulphur 
Phosphorous 
I. 
II. 
Per  cent. 
(") 
25.34 
Per  cent. 
(a) 
26.48 
65.81 
65.  84 
8.85 
7.68 
.80 
.71 
.008 
.005 
III. 
Per  cent. 
(a) 
26.86 
67.88 
5.26 
.64 
.003 
a  Not  determined. 
