VAN   HISE.J 
EASTERN    UNITED    STATES.  809 
comes  predominant.  At  Bonaparte  lake  a  contact  of  the  gabbro  with 
the  limestone  was  found  which  showed  all  the  characteristics  of  an  in- 
trusive rock,  the  limestone  giving  evidence  of  contact  action.  There 
were  found,  both  in  the  limestone  and  in  the  gabbro  areas,  smaller  areas 
of  coarse  red  granite. 
As  a  result  of  fche  reconnaissance  it  was  concluded  as  probable  that 
the  Adirondack*  core  is  an  eruptive  basic  rock,  which  has  upthrust  and 
intruded  itself  within  the  gneissic  series.  Because  of  the  character  of 
the  gneissic  series,  containing  quartz-schist,  graphitic  schist,  and 
crystalline  limestone,  including  graphite,  it  is  regarded  as  having  been 
originally  clastic.  Its  present  crystalline  character  and  quaquaversal 
arrangement  is  doubtless  due  to  the  intrusion  of  the  gabbro.  It  thus 
appears  that  there  is  in  this  region  a  great  bedded  succession  which 
belongs  to  the  Algonkian  system.  The  lowest  coarse  grained  gneiss 
inferior  to  the  limestone  perhaps  belongs  to  a  still  earlier  series,  but 
this  is  a  point  upon  which  closer  studies  are  needed. 
LITERATURE   OF  NEW   JERSEY. 
Vanuxem  and  Keating,131  in  1821,  state  that  the  country  around 
Franklin  is  composed  of  syenite  which  is  found  in  beds  or  layers  of  varia- 
ble thickness,  running  in  a  direction  parallel  to  that  of  the  ridge.  A  white 
limestone  forms  a  bed  with  eminently  crystalline  structure,  the  inclina- 
tion, direction,  and  dip  of  which  are  the  same  as  those  of  the  syenite. 
This  limestone  has  been  traced  for  a  distance  of  8  miles,  and,  although 
the  limestone  is  subordinate  to  the  syenite,  masses  of  the  latter  are  found 
in  it.  At  Franklin,  next  to  the  syenite,  are  found  masses  of  gray  wacke, 
which,  on  the  road  from  Franklins  to  Dr.  Fowler's,  is  seen  to  be  super- 
imposed upon  the  syenite  and  is  evidently  a  later  formation.  About 
a  quarter  of  a  mile  below  the  furnace  it  is  covered  with  a  violet  lime- 
stone which  rests  upon  it  in  parallel  superposition.  This  limestone  and 
that  associated  with  the  syenite  are  not  of  contemporaneous  origin, 
but  the  blue  limestone  is  a  real  mantle-formed  superposition. 
Pierce,132  in  1822,  describes  the  Highland  ranges  as  primitive,  with 
the  exception  of  an  isolated  transition  region.  The  rocks  here  included 
are  granite,  gneiss,  and  syenite,  while  in  the  transition  are  found  gray- 
wacke,  gray  wacke- slate,  chlorite- slate,  and  limestone. 
Bogers  (H.  D.),133  in  1840,  gives  a  systematic  account  of  the  Primary 
rocks  of  New  Jersey.  These  are  almost  exclusively  of  the  stratified 
class,  consisting  of  gneiss  under  all  its  forms,  the  granitoid  variety 
predominating.  Innumerable  small  veins  of  feldspathic  granite,  sye- 
nite, greenstone,  etc.,  penetrate  the  gneiss.  The  gneiss  is  comparatively 
seldom  of  the  schistose  kind.  Mica  is  deficient,  the  usual  mixture  be- 
ing either  feldspar  or  quartz  with  a  little  mica,  or  these  minerals  with 
an  excess  of  hornblende,  and  hornblende  and  magnetic  oxide  of  iron, 
the  latter  being  so  abundant  as  to  be  a  characteristic  constituent.  It 
occurs  not  only  as  an  occasional  ingredient  of  the  gneiss,  but  in  great 
