﻿1 
  66 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  Old 
  till. 
  As 
  far 
  as 
  the 
  writer 
  is 
  informed, 
  the 
  first 
  one 
  to 
  

   recognize 
  Prewisconsin 
  till 
  in 
  New 
  York 
  was 
  F. 
  B. 
  Taylor. 
  In 
  the 
  

   summer 
  of 
  1905 
  he 
  directed 
  attention 
  to 
  the 
  very 
  compact, 
  resistant, 
  

   stony^ 
  blue 
  till 
  in 
  the 
  bottom 
  of 
  the 
  deep 
  valleys 
  southeast 
  of 
  Buf- 
  

   falo, 
  which 
  he 
  confidently 
  pronounced 
  older 
  than 
  the 
  overlying 
  and 
  

   prevailing 
  Wisconsin 
  drift. 
  Subsequently 
  the 
  writer 
  noted 
  other 
  

   occurrences 
  of 
  similar 
  till. 
  In 
  1907 
  Frank 
  Carney 
  published 
  an 
  ac- 
  

   count 
  of 
  what 
  he 
  regarded 
  as 
  old 
  till 
  in 
  the 
  Keuka 
  valley.^ 
  

  

  No 
  soil 
  zones 
  or 
  forest 
  grounds 
  lying 
  between 
  the 
  supposed 
  old 
  

   till 
  and 
  the 
  superfical 
  till 
  have 
  yet 
  been 
  found, 
  to 
  prove 
  the 
  fact 
  of 
  

   an 
  interval 
  of 
  deglaciation, 
  though 
  such 
  finds 
  may 
  be 
  expected. 
  

   The 
  writer 
  has 
  noted 
  very 
  sharp 
  distinctions 
  between 
  the 
  two 
  tills, 
  

   with 
  incorporation 
  of 
  the 
  lower 
  into 
  the 
  upper. 
  An 
  important 
  

   locality 
  is 
  along 
  the 
  new 
  cuttings 
  for 
  the 
  shortened 
  tracks 
  of 
  the 
  

   Delaware 
  and 
  Hudson 
  Railroad 
  west 
  of 
  Schenectady, 
  between 
  Kelly 
  

   station 
  and 
  Duanesburg. 
  Here 
  an 
  incoherent, 
  yellow 
  till, 
  capped 
  

   with 
  gravel, 
  directly 
  overlies 
  a 
  very 
  hard, 
  dark 
  blue 
  till. 
  The 
  con- 
  

   trast 
  between 
  the 
  t^vo 
  is 
  very 
  striking 
  and 
  the 
  line 
  of 
  separation 
  is 
  

   very 
  distinct 
  in 
  some 
  sections; 
  while 
  in 
  places 
  the 
  older 
  blue 
  till 
  

   has 
  been 
  plowed 
  up 
  and 
  masses 
  hav^ 
  become 
  incorporated 
  in 
  the 
  

   yellow 
  till. 
  The 
  blue 
  till 
  retains 
  its 
  color 
  and 
  consistency 
  even 
  when 
  

   exposed 
  for 
  considerable 
  time 
  to 
  the 
  weather, 
  masses 
  which 
  have 
  

   lain 
  in 
  the 
  field 
  over 
  the 
  winter 
  being 
  only 
  partially 
  disintegrated. 
  

   The 
  writer 
  was 
  told 
  that 
  the 
  steam 
  shovels 
  were 
  able 
  to 
  cut 
  the 
  

   blue 
  '' 
  hardpan 
  '' 
  with 
  much 
  difficulty 
  and 
  ver}^ 
  slowly. 
  

  

  The 
  blue 
  til 
  has 
  a 
  very 
  different 
  composition 
  and 
  derivation 
  

   from 
  the 
  overlying 
  and 
  oxidized 
  yellow 
  till. 
  It 
  is 
  impossible 
  that 
  

   an 
  ice 
  sheet, 
  producing 
  from 
  its 
  burden 
  of 
  ground-up 
  shale 
  and 
  

   limestone 
  the 
  hard 
  blue 
  till, 
  should 
  suddenly 
  cease 
  to 
  deposit 
  this 
  

   and 
  at 
  once 
  lay 
  down 
  a 
  yellow 
  oxidized 
  till 
  of 
  entirely 
  different 
  

   origin. 
  We 
  have 
  here 
  good 
  proof 
  of 
  at 
  least 
  two 
  distinct 
  episodes 
  

   in 
  ice 
  work. 
  

  

  The 
  writer 
  has 
  not 
  noted 
  in 
  our 
  Thousands 
  Islands 
  area 
  any 
  

   example 
  of 
  tills 
  comparable 
  to 
  the 
  old, 
  blue 
  tills 
  farther 
  south, 
  

   though 
  Gushing 
  thinks 
  that 
  he 
  has 
  seen 
  them. 
  But 
  they 
  probably 
  

   do 
  occur 
  just 
  south 
  of 
  the 
  boundary, 
  in 
  the 
  northern 
  part 
  of 
  the 
  city 
  

   of 
  Watertown. 
  Here 
  begins 
  a 
  group 
  of 
  drumlins 
  that 
  extends 
  

   southward. 
  In 
  the 
  mass 
  of 
  the 
  drumlin 
  forming 
  the 
  dome-shaped 
  

   hill 
  north 
  of 
  the 
  Black 
  river, 
  and 
  in 
  the 
  small 
  drumlin 
  ridge 
  in 
  the 
  

   northwest 
  corner 
  of 
  the 
  citv, 
  where 
  the 
  Dexter 
  electric 
  line 
  crosses 
  

  

  1 
  Pre-Wisconsin 
  Drift 
  in 
  the 
  Finger 
  Lake 
  Region 
  of 
  New 
  York. 
  Jour. 
  

   Geol. 
  15:571-85. 
  

  

  i 
  

  

  I 
  

  

  