﻿586 
  Forty-seventh 
  Report 
  on 
  the 
  State 
  Museum. 
  

  

  The 
  clays 
  are 
  of 
  two 
  kinds, 
  the 
  blue 
  and 
  yellow. 
  The 
  blue 
  

   clays 
  are 
  the 
  lowest, 
  nearly 
  every 
  outcrop 
  of 
  blue 
  clay 
  being 
  cov- 
  

   ered 
  by 
  a 
  mantle 
  of 
  stratified 
  yellow 
  clay. 
  These 
  rest 
  either 
  

   upon 
  cross-bedded 
  glacial 
  sands 
  or 
  directly 
  upon 
  the 
  rocks, 
  usually 
  

   of 
  the 
  Hudson 
  River 
  group. 
  

  

  Little 
  in 
  addition 
  to 
  Mr. 
  Heinrich 
  Ries' 
  work 
  in 
  the 
  local 
  

   descriptions 
  of 
  individual 
  claybanks 
  or 
  upon 
  the 
  deposits 
  of 
  the 
  

   quaternary 
  in 
  the 
  Hudson 
  River 
  valley 
  need 
  be 
  given 
  here. 
  The 
  

   work 
  has 
  been 
  done 
  excellently 
  and 
  for 
  this 
  the 
  reader 
  is 
  referred 
  

   to 
  the 
  tenth 
  annual 
  report 
  of 
  the 
  State 
  Geologist 
  for 
  1890, 
  page 
  110 
  

   et 
  seq. 
  What 
  can 
  be 
  done 
  is 
  to 
  call 
  attention 
  to 
  the 
  probable 
  

   extension 
  of 
  this 
  formation 
  into 
  the 
  interior 
  of 
  the 
  county. 
  

  

  At 
  Wilbur, 
  on 
  Rondout 
  creek, 
  one 
  mile 
  above 
  Rondout, 
  are 
  

   immense 
  sandbanks 
  at 
  least 
  one 
  hundred 
  feet 
  high. 
  The 
  sand 
  

   here 
  is 
  well 
  stratified, 
  and 
  lies 
  in 
  alternate 
  beds 
  or 
  lenses 
  of 
  vary- 
  

   ing 
  degrees 
  of 
  fineness. 
  There 
  are 
  large 
  quantities 
  of 
  this 
  sand 
  

   removed 
  every 
  year, 
  and 
  used 
  principally 
  in 
  tempering 
  bricks 
  in 
  

   the 
  yards 
  above 
  Rondout. 
  The 
  excavation 
  is 
  made 
  in 
  a 
  Y-shaped 
  

   cut 
  so 
  that 
  the 
  sand 
  is 
  constantly 
  running 
  in 
  from 
  the 
  top. 
  The 
  

   cut 
  in 
  the 
  deepest 
  part 
  is 
  yet 
  at 
  leasr, 
  twenty-five 
  feet 
  above 
  the 
  

   level 
  of 
  the 
  river. 
  It 
  seems 
  very 
  probable 
  that 
  these 
  sands 
  over- 
  

   lie 
  deposits 
  of 
  clay, 
  but 
  no 
  trace 
  of 
  it 
  is 
  to 
  be 
  seen. 
  Farther 
  up 
  

   the 
  stream, 
  near 
  the 
  West 
  Shore 
  railroad 
  bridge, 
  rocks 
  come 
  to 
  

   the 
  edge 
  of 
  the 
  river. 
  From 
  this 
  point 
  up 
  there 
  is 
  no 
  chance 
  for 
  

   either 
  sand 
  or 
  clay 
  deposits 
  to 
  exist 
  except 
  in 
  a 
  few 
  depressions 
  

   of 
  limited 
  extent. 
  One 
  pocket 
  of 
  this 
  kind 
  is 
  well 
  exposed 
  at 
  

   Le 
  Fever 
  Falls. 
  This 
  point 
  is 
  a 
  little 
  more 
  than 
  eight 
  miles 
  from 
  

   Kingston 
  on 
  Rondout 
  creek. 
  The 
  deposit 
  is 
  fat 
  yellow 
  clay 
  well 
  

   stratified, 
  about 
  ten 
  feet 
  thick 
  and 
  about 
  thirty 
  feet 
  wide 
  where 
  

   worked. 
  It 
  is 
  covered 
  with 
  well 
  stratified 
  sand 
  and 
  light 
  gravels. 
  

   Judging 
  from 
  the 
  contour 
  of 
  the 
  country 
  this 
  deposit 
  must 
  cover 
  

   a 
  good 
  many 
  acres. 
  The 
  clay 
  rests 
  on 
  the 
  Cauda-galli 
  grit. 
  The 
  

   altitude 
  of 
  this 
  point 
  is 
  not 
  known 
  but 
  it 
  must 
  be 
  considerably 
  

   over 
  300 
  feet. 
  

  

  No 
  other 
  deposit 
  has 
  been 
  observed, 
  but 
  along 
  the 
  valleys 
  of 
  

   the 
  Rondout 
  and 
  of 
  the 
  Walkill 
  rivers 
  there 
  are 
  large 
  banks 
  of 
  

   well 
  stratified 
  sands. 
  There 
  are, 
  no 
  doubt, 
  many 
  places 
  where 
  

   clays 
  have 
  been 
  deposited 
  to 
  a 
  greater 
  or 
  less 
  extent. 
  Just 
  at 
  

   present, 
  however, 
  these 
  additional 
  deposits 
  are 
  not 
  needed 
  for 
  

  

  