622  PRE-CAMBJRTAN    GEOLOGY    OF    NORTH   AMERICA. 
SECTIOK  2.     SOUTHEASTERN  NEW  YORK. 
SUMMARY  OF  LITERATURE. 
Pierce,02  in  1818,  describes  the  nucleus  of  Staten  Island  as  consist- 
ing of  steatite,  which  stamps  the  formation  as  Primitive. 
Akerly,03  in  1820,  describes  a  section  running  from  Long  Branch, 
in  New  Jersey,  northward  to  New  Marlboro,  Ulster  County,  N.  Y. 
The  rocks  included  are  divided  into  principal  rocks,  metalliferous 
rocks,  basaltic  rocks,  and  alluvial  formations,  which  correspond  to  the 
German  terms  Primitive,  Transition,  Floetz,  and  Alluvial.  Staten 
Island  has  a  rocky  base  composed  of  the  magnesian  order  of  rocks, 
consisting  of  serpentine  and  steatites  or  soapstones.  Hoboken  is  of 
the  same  nature  as  Staten  Island.  The  Plighlands  of  New  York  con- 
sist of  granitic  rocks  belonging  to  the  Primitive  class.  Gneiss  and 
micaceous  schist  are  the  most  prominent ;  but  granite,  properly  speak- 
ing, also  enters  into  the  composition.  The  commencement  or  termi- 
nation of  any  of  these  rocks  has  not  been  found,  and  as  they  graduate 
into  one  another  they  are  considered  the  same  formation.  At  Hell 
Gate  the  rocks  are  gneiss  and  micaceous  schist.  The  northern  part 
of  New  York  Island  is  of  the  Primitive  formation  and  includes  gran- 
ite, gneiss,  and  limestone.  Crystalline  limestone  is  also  found  at 
other  points.  All  these  rocks  are  placet1  in  the  Primitive  formation, 
and  they  contain  no  organic  remains. 
Eaton,64  in  1822,  describes  as  occurring  in  the  Highlands  of  the 
Hudson,  without  reference  to  order  of  time,  gneiss,  hornblende  rocks, 
and  argillite.     The  gneiss  appears  to  be  the  center  or  oldest  forma 
tion. 
Mather,05  in  1838,  mentions  gneiss  on  Long  Island ;  granite  and 
serpentine  on  Staten  Island ;  and  granite,  gneiss,  and  granular  quartz 
in  the  southeastern  part  of  Dutchess  County.  In  the  serpentine  was 
observed  a  trap  rock. 
Mather,60  in  1839,  describes  the  rocks  of  New  York,  Westchester, 
and  Putnam  counties  as  comprising  granite,  gneiss,  mica  slate,  quartz 
rock,  talcose  slate,  limestone,  syenite,  serpentine,  steatite,  augite  rock, 
and  greenstone,  the  latter  traversing  the  other  rocks  like  veins  or 
being  interstratified  with  them.  The  gneiss  and  granitoid  rocks  are 
distinctly  stratified,  as  is  also  the  limestone. 
Horton,0,7  in  1839,  describes  the  Primitive  rocks  of  Orange  County 
as  less  regular  in  stratification  and  dip  along  the  banks  of  the  Hud- 
son and  at  their  western  margin  than  in  their  center.  The  strike  of 
the  Primitive  gneiss  is  about  northeast-southwest,  with  a  dip  to  the 
southeast  from  45°  to  nearly  vertical.  Interstratified  among  the 
Primitive  rocks  are  hornblende  rock  and  white  limestone.  Argillite 
is  placed  with  the  Transition  formations. 
Gale,08  in  1839,  finds  that  the  rocks  of  New  York  County  are  chiefly 
a  gneiss,  associated  with  which  as  subordinate  rocks  are  serpentine, 
