﻿152 
  , 
  NEW 
  TOEK 
  STATE 
  MUSEUM 
  

  

  upon 
  the 
  Hudson 
  river 
  schists. 
  This 
  is 
  probably 
  equivalent 
  to 
  

   the 
  Oneida 
  conglomerate, 
  or 
  possibly 
  the 
  base 
  of 
  the 
  Medina 
  

   group. 
  

  

  The 
  source 
  from 
  which 
  such 
  enormous 
  quantities 
  of 
  rolled 
  

   pebbles 
  of 
  quartz 
  could 
  have 
  been 
  derived 
  and 
  the 
  mode 
  by 
  

   which 
  they 
  could 
  have 
  been 
  sppead 
  so 
  widely 
  over 
  a 
  sea 
  bottom 
  

   is 
  a 
  very 
  obscure 
  question 
  in 
  geology. 
  Several 
  other 
  such 
  forma- 
  

   tions 
  of 
  conglomerate 
  are 
  known, 
  two 
  of 
  Tv^hich 
  occur 
  at 
  the 
  

   lower 
  and 
  middle 
  parts 
  of 
  the 
  Carboniferous 
  system. 
  

  

  Medina 
  Sandstone 
  

  

  The 
  next 
  succeeding 
  group 
  is 
  that 
  named 
  from 
  a 
  village 
  in 
  Or- 
  

   leans 
  county 
  where 
  it 
  is 
  w^ell 
  exposed. 
  

  

  It 
  is 
  a 
  huge 
  mass 
  of 
  sandy 
  and 
  shaly 
  rock, 
  of 
  very 
  variable 
  

   hardness 
  from 
  soft 
  marl 
  to 
  hard 
  sandstone, 
  and 
  varying 
  in 
  color 
  

   from 
  deep 
  red 
  to 
  olive 
  and 
  light 
  gray. 
  It 
  is 
  not 
  known 
  in 
  the 
  far 
  

   west, 
  seeming 
  to 
  thin 
  out 
  and 
  disappear 
  before 
  reaching 
  Wiscon- 
  

   sin, 
  but 
  is 
  well 
  seen 
  on 
  the 
  Niagara 
  river, 
  where 
  it 
  forms 
  most 
  of 
  

   the 
  precipice 
  near 
  Lewiston. 
  At 
  this 
  point 
  the 
  low^er 
  part 
  is 
  a 
  

   soft 
  red 
  shale, 
  with 
  harder 
  and 
  lighter 
  colored 
  layers 
  above, 
  to 
  

   one 
  heavy 
  bed 
  of 
  which 
  the 
  cables 
  of 
  the 
  Lewiston 
  suspension 
  

   bridge 
  are 
  fastened. 
  This 
  sandstone 
  may 
  also 
  be 
  seen 
  in 
  the 
  

   lower 
  part 
  of 
  the 
  river 
  cliffs, 
  extending 
  as 
  far 
  as 
  the 
  upper 
  

   Suspension 
  Bridge. 
  The 
  same 
  rock 
  is 
  quarried 
  near 
  the 
  lower 
  

   part 
  of 
  Lockport 
  for 
  building 
  and 
  flagstone, 
  and 
  it 
  forms 
  the 
  lower 
  

   falls 
  of 
  the 
  Genesee 
  at 
  Kochester, 
  at 
  the 
  top 
  of 
  which 
  the 
  hard 
  

   uppermost 
  layer, 
  called 
  the 
  ^ 
  Gray 
  band,' 
  is 
  very 
  conspicuous 
  from 
  

   its 
  light 
  color. 
  Further 
  east, 
  the 
  same 
  rock 
  forms 
  the 
  falls 
  of 
  the 
  

   Oswego 
  river 
  at 
  Fulton; 
  but 
  in 
  the 
  Mohawk 
  valley 
  it 
  thins 
  out, 
  

   and 
  disappears. 
  In 
  southeastern 
  New 
  York, 
  however, 
  near 
  Ron- 
  

   dout, 
  it 
  re-appears 
  and 
  is 
  very 
  thick 
  at 
  the 
  Delaware 
  water 
  gap 
  

   in 
  New 
  Jersey 
  and 
  Pennsylvania, 
  reaching, 
  in 
  the 
  latter 
  state, 
  

   the 
  thickness 
  of 
  1,000 
  feet; 
  and 
  it 
  may 
  be 
  recognized 
  as 
  far 
  south 
  

   as 
  Alabama. 
  

  

  