NEW    ENGLAND.  553 
Hitchcock  (C.  H.),5  in  1862,  describes  the  rocks  of  the  southern 
part  of  the  State  as  granite  and  syenite,  gneiss  and  mica  schist,  saccha- 
roidal  Azoic  limestone,  quartz  rock  (Taconic),  eolian  limestone, 
etc.  Presumably  the  granite  and  syenite,  gneiss  and  mica  schist, 
and  Azoic  limestone  are  Primitive.  In  the  Kennebec  Valley  are 
found  interstratified  limestones  and  slates,  the  cleavage  of  which  is 
almost  transverse  to  the  bedding,  so  that  it  is  possible  to  get  at  the 
true  direction  of  lamination  only  by  following  the  limestone  belts. 
At  one  place  is  an  abrupt  change  from  mica  schist  to  granite.  A  red 
conglomerate  rests  unconformably  upon  a  slate  at  Woodstock. 
Hitchcock  (C.  H.),c  in  1874,  describes  three  groups  of  rocks  at 
Portland,  the  oldest  of  which  is  the  Huronian.  In  this  system  are 
green  talcose  schists,  hornblendic  schist,  micaceous  and  plumbaceous 
schist,  and  other  varieties.  They  are  referred  to  the  Huronian  on  the 
ground  that  such  rocks  are  typical  of  this  period  and  that  continuity 
of  mineral  character  indicates  similarity  of  age  till  otherwise  proved. 
Huntington,7  in  1878,  describes  the  region  about  the  headwaters 
of  Androscoggin  River.  The  rocks  are  classified  as  Laurentian, 
Huronian,  and  Paleozoic.  In  the  Laurentian  is  gneiss  containing 
limestone.  In  the  Huronian  are  White  Mountain  gneisses  and  schists, 
mica  schists  with  staurolite,  chloride  and  whitish  argillitic  mica 
schists,  sandstone  schists,  diabase,  diorite  with  serpentine,  argillitic 
mica  schists  with  staurolite,  and  Rangely  conglomerates.  In  the 
Rangely  conglomerate,  when  freshly  broken,  every  portion  of  it  ex- 
cept the  pebbles  resembles  in  all  respects  the  staurolitic  schist.  Cross- 
ing the  strata  are  belts  in  which  the  pebbles  are  wanting,  or  have 
been  so  changed  that  they  are  not  apparent,  although  locally  the 
fragments  of  the  conglomerate  are  a  foot  in  diameter.  Granite, 
diorite,  and  felsite  are  placed  among  the  eruptive  rocks. 
SECTION  2.     NEW  HAMPSHIRE. 
SUMMARY  OF  LITERATURE. 
Jackson,8  in  1841,  in  a  general  consideration  of  the  geology  of  the 
State,  says  that  granite  is  an  igneous  rock  and  is  the  foundation  on 
which  all  the  more  recent  formations  rest.  When  it  is  found  cutting 
other  rocks  the  intense  heat  has  often  metamorphosed  the  adjacent 
rocks  for  considerable  distances.  Reposing  directly  on  the  granite  is 
found  gneiss,  the  origin  of  which  is  undetermined.  By  some  geologists 
gneiss  is  considered  a  metamorphic  rock:  others  suppose  thai  it- 
stratified  structure  is  due  to  the  crystallization  in  laminae  ami  that  it 
is  merely  the  upper  crust  of  granite.  Above  the  gneiss  are  found 
mica  slate,  chlorite  slate,  and  argillaceous  slate,  which  are  regarded 
as  metamorphic  rocks.  Slates  and  granite  alternate  with  each  other, 
and  this  is  due  to  the  subsequent   intrusion  of  granite.     There  have 
