274               CONTRIBUTIONS    TO    ECONOMIC    GEOLOGY,    1903.  [bull. 225. 
Section  of  Durham  coal  on  //anas  Creek. 
Shale  roof.                                                                                                             Ft.  In. 
Coal 2  6 
Shale 0  1 
Coal - --  1  6 
Total 4  1 
Section  of  Durham  coal  on  Williams  Creek. 
Shale  roof.                                                                                              .       Ft.  In. 
Coal 1  3 
Shale,  black 0  1J 
Coal - 2  0 
Shale,  black 0  3 
Coal 0  6 
Fire  clay,  dark  drab 1  6 
Shale,  black 0  6 
Coal 1  6 
Total 7     7 
Howard  coal. — Below  the  sandstone  so  prominent  on  Clover  Fork 
is  an  interval  of  shale  containing  several  coals,  which  are  usually  thin 
and  often  of  the  cannel  variety.  In  a  few  places  one  of  these  coals 
reaches  workable  thickness,  as  near  the  mouth  of  Wallin  Creek,  where 
it  shows  the  following  section: 
Section  of  Howard  coal  on  Terry  Creek. 
Shale  roof.                                                                                                     Ft.  In. 
Coal,  cannel 2  0 
Coal,  bituminous 2  0 
Total 4      0 
Rohbins  coal. — Between  Yellow  Creek  and  Brownies  a  coal  betweer 
the  horizons  of  the  Howard  and  Durham  coals  reaches  workable 
thickness,  as  shown  by  the  two  following  sections: 
Section  of  Robbins  coal  on  Crane  Creek. 
Shale  roof.  Ft.    In. 
Coal 3     10 
Section  of  Robbins  coal  on  Hances  Creek. 
Shale  roof.                                                                                                     Ft.  In. 
Coal 2  0 
Clay 0  1 
Coal 1  3 
Total 3      4 
QUALITY    OF    COAL. 
^  The  quality  of  the  coals  in  the  eastern  part  of  the  Cumberland  Gar. 
field  is  indicated  in  the  following  table  of  analyses;  samples  obtained 
by  McCreath  and  d'Invilliers,  analyses  by  McCreath: 
