﻿T. 
  BELT 
  ON 
  THE 
  STEPPES 
  OF 
  SIBERIA. 
  

  

  491 
  

  

  in 
  the 
  river-bank 
  are 
  about 
  60 
  feet 
  thick, 
  as 
  

   shown 
  in 
  fig. 
  2. 
  The 
  lowest 
  bed 
  exposed 
  is 
  a 
  

   finely 
  laminated 
  silt, 
  which, 
  in 
  drying, 
  sets 
  to 
  

   an 
  almost 
  stony 
  consistency, 
  but 
  immediately 
  

   disintegrates 
  when 
  placed 
  in 
  water 
  ; 
  the 
  bottom 
  

   of 
  this 
  bed 
  is 
  not 
  seen. 
  Above 
  it 
  lies 
  a 
  bed 
  of 
  

   laminated 
  sand, 
  mostly 
  clean, 
  but 
  in 
  some 
  parts 
  

   mixed 
  with 
  silt; 
  in 
  others 
  it 
  is 
  false-bedded. 
  

   It 
  is 
  nearly 
  similar 
  to 
  that 
  near 
  Ischim, 
  ex- 
  

   cepting, 
  that 
  I 
  found 
  in 
  it 
  some 
  lines 
  of 
  small 
  

   pebbles 
  and 
  broken 
  and 
  worn 
  shells 
  of 
  Cyrena 
  

   fiuminalis. 
  None 
  of 
  the 
  pebbles 
  were 
  larger 
  

   than 
  a 
  small 
  cherry. 
  

  

  From 
  Omsk 
  to 
  Pavlodav, 
  a 
  distance 
  of 
  253 
  

   miles, 
  our 
  course 
  lay 
  up 
  the 
  right 
  bank 
  of 
  the 
  

   Irtisch, 
  and 
  the 
  sections 
  everywhere 
  showed 
  a 
  

   similar 
  arrangement 
  of 
  the 
  beds 
  of 
  sand 
  and 
  

   silt 
  as 
  had 
  been 
  exposed 
  at 
  Omsk. 
  At 
  one 
  

   point, 
  about 
  100 
  miles 
  from 
  Omsk, 
  I 
  noticed 
  

   that 
  the 
  lines 
  of 
  pebbles 
  were 
  getting 
  more 
  

   numerous 
  and 
  a 
  little 
  larger, 
  some 
  occurring 
  

   as 
  big 
  as 
  a 
  walnut. 
  In 
  none 
  of 
  these 
  sections 
  

   was 
  the 
  bottom 
  of 
  the 
  steppe 
  strata 
  seen, 
  nor 
  

   of 
  course 
  the 
  bed-rock 
  on 
  which 
  they 
  rested, 
  

   until 
  I 
  reached 
  the 
  town 
  of 
  Pavlodav, 
  in 
  lat. 
  

   52° 
  20' 
  N., 
  where, 
  on 
  the 
  river-bank, 
  I 
  found 
  

   the 
  whole 
  of 
  the 
  strata 
  cut 
  through 
  down 
  to 
  

   the 
  bed-rock 
  (fig. 
  3). 
  This 
  rock 
  (No. 
  6 
  in 
  

   fig. 
  3) 
  was 
  magnesian 
  limestone, 
  which 
  at 
  the 
  

   top 
  was 
  crushed 
  and 
  broken, 
  and 
  seemed 
  to 
  

   graduate 
  from 
  broken 
  rock 
  through 
  broken 
  rock 
  

   mixed 
  with 
  fine 
  silt, 
  into 
  fine 
  silt, 
  in 
  which 
  

   were 
  numerous 
  blocks 
  of 
  the 
  bed-rock. 
  The 
  

   bed 
  of 
  silt 
  was 
  unlaminated, 
  and 
  about 
  6 
  feet 
  

   thick 
  ; 
  in 
  its 
  upper 
  half 
  it 
  did 
  not 
  contain 
  any 
  

   pieces 
  of 
  the 
  bed-rock. 
  It 
  was 
  followed 
  by 
  15 
  

   feet 
  of 
  clean 
  coarse 
  sand, 
  laminated, 
  and 
  in 
  some 
  

   parts 
  false-bedded. 
  It 
  contained 
  thin 
  layers 
  of 
  

   small 
  gravel; 
  and 
  at 
  the 
  point 
  marked 
  x 
  in 
  

   section 
  there 
  was 
  a 
  line 
  of 
  subangular 
  pebbles, 
  

   some 
  of 
  which 
  were 
  as 
  large 
  as 
  a 
  man's 
  fist. 
  

   This 
  bed 
  was 
  followed 
  by 
  8 
  feet 
  of 
  light-coloured 
  

   sandy 
  silt, 
  and 
  the 
  whole 
  capped 
  by 
  20 
  feet 
  of 
  

   stratified 
  reddish-brown 
  sand 
  containing 
  lines 
  

   of 
  small 
  gravel. 
  

  

  At 
  Pavlodav 
  we 
  crossed 
  the 
  river 
  and 
  the 
  

   alluvial 
  plain, 
  which 
  is 
  6 
  miles 
  wide 
  and 
  was 
  

   covered 
  with 
  hay 
  ; 
  we 
  then 
  struck 
  across 
  the 
  

   country 
  to 
  the 
  south-south-west. 
  After 
  leaving 
  

   the 
  river 
  there 
  were 
  no 
  natural 
  sections 
  of 
  the 
  

  

  

  9 
  

  

  era" 
  

  

  &5 
  

  

  

  3 
  

  

  _ 
  — 
  -e! 
  

  

  55 
  

  

  

  

  "EL 
  

  

  «> 
  

  

  5* 
  

  

  *S 
  

  

  

  

  5' 
  

  

  a 
  

  

  

  Co" 
  

  

  

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  >" 
  

  

  2 
  3i 
  2 
  

  

  