NEW   ENGLAND.  561 
Metamorphism  is  made  to  apply  to  any  transformation  of  any  kind 
of  rock  into  another.  At  Newport,  R.  I.,  and  East  Wallingford  and 
Plymouth,  Vt.,  are  found  schist  conglomerates  in  which  the  pebbles 
are  elongated  very  much  in  the  direction  of  their  strike.  They  are 
flattened,  but  not  so  strikingly  as  elongated,  are  indented  deeply 
into  one  another,  are  sometimes  a  good  deal  bent,  and  are  cut  across 
by  parallel  joints  and  fissures.  At  times  the  process  has  gone  so  far 
as  to  merge  the  pebbles  together,  so  that  they  scarcely  present  the 
appearance  of  ordinary  pebbles.  If  the  talcose  conglomerate  schist 
is  looked  at  on  the  edge  corresponding  to  the  dip,  nothing  is  seen  but 
alternate  folia  of  quartz  and  talc  and  mica,  and  the  rock  would  be 
pronounced  a  good  example  of  a  talcose  schist.  But  a  fracture  at 
right  angles  reveals  the  flattened  pebbles  and  shows  that  what  have 
been  regarded  as  folia  are  their  edges.  If  the  process  of  flattening 
had  been  carried  a  little  further  no  evidence  would  remain  that  they 
were  ever  pebbles.  How  extensively  the  process  has  been  operative, 
thus  producing  schists  and  gneisses  from  conglomerates  in  the  Green 
Mountains,  is  unknown.  No  examples  of  undoubted  pebbles  in  a 
gneiss  have  been  found. 
At  Whately,  Mass.,  on  Ascutney,  and  at  Barnet  and  Granby,  Vt., 
are  conglomerates  which  have  as  a  matrix  granite  and  porphyry. 
The  granite  sometimes  passes  into  syenite.  At  Ascutney  the  syenite 
abounds  in  black,  rounded  masses  which  are  for  the  most  part  crys- 
talline hornblende  and  feldspar,  and  are  probably  transmuted  peb- 
bles. At  Granby  the  pebbles,  manifestly  rounded,  are  either  mica 
schist  or  white,  almost  hyaline,  quartz,  just  such  as  form  the  pebbles 
in  the  conglomerates  at  Wallingford  and  Plymouth,  and  the  base  is  a 
fine-grained  syenite,  passing  sometimes  almost  into  mica  schist.  A 
pebble  of  hornblende  schist  is  also  sometimes  seen.  In  bowlders  of 
this  conglomerate  found  at  Northampton,  Mass.,  and  probably  de- 
rived from  Whately,  the  most  abundant  pebbles  are  those  of  the 
brown  sandstone,  considerably  metamorphosed  and  flattened.  Those 
of  hornblende  schist  are  common.  Sometimes  they  are  merely  crys- 
talline hornblende,  not  foliated  generally,  however,  but  mixed  with 
some  feldspar ;  and  they  may  become  syenite,  and  are  frequently  por- 
phyritic  by  distinct  crystals  of  feldspar.  The  cement  is  syenite, 
often  more  hornblendic  than  usual.  When  the  pebbles  are  highly 
crystallized  they  become  so  incorporated  with  the  matrix  that  it  is 
difficult  to  separate  them  with  a  smooth  surface,  and  apparently  they 
pass  insensibly  into  those  rounded  nodules,  chiefly  hornblendic,  so 
common  in  syenite,  especially  that  of  Ascutney.  These  occurrences 
are  regarded  as  proof  that  the  completely  crystalline  granular  nmtrix 
is  a  metamorphic  rock. 
•       55721— Bull.  360—09 36 
