440  CONTRIBUTIONS    TO    ECONOMIC    GEOLOGY,  1903.  [bull. 225. 
about  halfway   down  the  bluff,  the  other  20  feet  lower.     Generally 
there  is  a  capping  of  the  red  loam  and  sands  of  the  Lafayette  over  the 
limestone,  but  near  the  upper  end  of  the  bluff  the  white  rock  extends 
to  the  summit,  where  it  has  a  capping  of  plastic  clay  only.     The  char-, 
acter  of  the  limestone  is  shown  in  analysis  28  (see  p.  446). 
At  Elm  Bluff,  as  has  already  been  shown,  the  upper  and  middle 
divisions  of  the  formation  are  in  contact.  At  Kings  Bluff  the  middle 
and  lower  parts  of  the  formation  are  in  contact.  At  the  other  bluff's 
of  the  river  between  Kings  Landing  and  Selma  the  rock  of  the  lower 
division  is  exhibited.  No.  31  is  an  analysis  of  the  material  as 
exposed  at  Cahaba;  No.  53  of  the  river  bluff  at  the  steamboat  landing 
in  Selma,  and  No.  32  at  Benton. 
To  summarize:  From  Demopolis  eastward  along  the  line  of  the 
Southern  Railway,  by  Van  Dorn,  Gallion,  Uniontown,  Massillon,  and 
thence  by  Martins  and  Milhouse  stations  to  White  Bluff,  the  white  or 
Demopolis  type  of  rock  appears  at  the  surface  in  clean  exposures  at 
almost  innumerable  points,  either  immediately  on  the  railroad  or  at 
very  short  distance  from  it.  So  far  as  the  quality,  quantity,  and 
accessibility  of  the  limestone  rock  are  concerned,  manufactories  of 
cement  might  be  located  almost  anywhere  in  this  territory.  From 
Demopolis  westward  the  same  conditions  prevail  up  the  river  to  Epes, 
and  thence  to  Gainesville,  beyond  which  point  the  white  rock  is  to  the 
west  of  the  river  at  greater  or  less  distance. 
East  of  Alabama  River  the  outcrop  of  the  cement  rock  is  crossed 
by  the  Louisville  and  Nashville  Railroad  (Repton  branch),  as  before 
stated,  between  Berlin  and  Pleasant  Hill  stations.  At  Benton,  on 
Alabama  River  and  on  the  railroad,  the  limestone  has  the  composition 
shown  by  analysis  32. 
On  the  Montgomery  and  Selma  road,  at  the  crossing  of  Pintlala 
Creek  near  Manack  station,  the  limestone  is  exposed  in  the  creek 
banks  and  in  the  open  fields,  often  with  little  or  no  overburden.  On 
page  446  is  given  an  analysis  of  a  specimen  from  the  fields  along  the 
wagon  road  (No.  33)  and  from  the  creek  bank  (No.  34). 
On  the ^naiii  branch  of  the  Louisville  and  Nashville  Railroad  the 
white  rock  shows  between  the  city  and  McGhees  switch,  and  an 
analysis  of  a  specimen  from  McGhees  is  given  (No.  35). 
Examinations  have  not  been  carried  beyond  Montgomery,  but  it  is 
known  that  the  white  prairie  rock  is  crossed  by  the  Central  of  Georgia 
Railroad  between  Matthews  and  Fitzpatrick  stations,  and  there  seems 
to  be  no  doubt  that  along  this  stretch  of  the  road  suitable  rock 
will  be  found  convenient  to  the  line. 
THE    ST.    STEPHENS   LIMESTONE. 
<1<  n<  nil  description. — The  St.  Stephens  or  White  limestone  forma- 
tion of  the  Alabama  Tertiary,  which  includes  the  uppermost  of  the 
