﻿and 
  

  

  V 
  

  

  the 
  Viscosity 
  of 
  Glacier 
  Ice. 
  

   9-46 
  /35800 
  2 
  x 
  19900 
  2 
  

  

  V 
  1 
  

  

  \x-G 
  

  

  107 
  

  

  G85 
  . 
  (23) 
  

  

  2 
  X 
  U-OOuOGoJ: 
  ° 
  V35«U'J 
  2 
  + 
  li)y00 
  2 
  y 
  

  

  = 
  125x 
  10 
  12 
  poises. 
  

  

  The 
  upper 
  curve 
  of 
  fig. 
  13 
  is 
  the 
  surface-speed 
  curve 
  

   calculated 
  by 
  the 
  formula 
  below, 
  

  

  w 
  

  

  i 
  

  

  .4__ 
  

  

  2 
  a 
  a 
  -r 
  ar^-ar 
  — 
  2x 
  2 
  4- 
  \x 
  -f 
  1. 
  

  

  It 
  will 
  be 
  seen 
  that 
  this 
  curve 
  very 
  closely 
  resembles 
  the 
  

   one 
  obtained 
  by 
  Weinberg 
  for 
  pitch. 
  

  

  "We 
  have 
  not 
  as 
  yet 
  obtained 
  the 
  formula 
  for 
  the 
  flux 
  of 
  

   Parr's 
  curve. 
  

  

  The 
  great 
  defect 
  of 
  the 
  ellipse 
  as 
  a 
  basis 
  for 
  comparison 
  

   lies 
  in 
  the 
  fact 
  that 
  the 
  boundary 
  is 
  vertical 
  at 
  the 
  sides 
  (for 
  

   the 
  solution 
  has 
  only 
  been 
  found 
  for 
  the 
  complete 
  semi-ellipse), 
  

   whilst 
  the' 
  sides 
  of 
  a 
  natural 
  valley 
  are 
  sloping. 
  This 
  makes 
  

   an 
  enormous 
  difference 
  to 
  the 
  shape 
  of 
  the 
  surface-velocity 
  

   curve 
  near 
  the 
  sides. 
  

  

  Summary. 
  — 
  Table 
  III. 
  gives 
  the 
  results 
  of 
  the 
  various 
  

   calculations 
  which 
  have 
  been 
  made 
  of 
  the 
  viscosity 
  of 
  glacier 
  

   ice, 
  with 
  the 
  names 
  of 
  the 
  experimentalists 
  and 
  dates. 
  

  

  Table 
  III. 
  

  

  Experimentalist. 
  

  

  Dr. 
  Main 
  

  

  McConnell 
  & 
  Kidd 
  

   Boris 
  Weinberg 
  .. 
  

   Bliimcke 
  & 
  Hess 
  .. 
  

   Tyndall 
  & 
  others 
  .. 
  

   Bliimcke 
  & 
  Hess 
  .. 
  

  

  Date. 
  

  

  1888 
  

   1888 
  

   1907 
  

   1907 
  

  

  1910 
  

  

  Calculated 
  by 
  

  

  Date. 
  

  

  R. 
  M. 
  Deeley 
  ... 
  

  

  1912 
  

  

  R. 
  M. 
  Deeley 
  ... 
  

  

  

  B. 
  Weinberg 
  

  

  1907 
  

  

  B. 
  Weinberg 
  

  

  1906 
  

  

  R. 
  M. 
  Deeley 
  ... 
  

  

  1908 
  

  

  B. 
  Weinberg 
  

  

  1910 
  

  

  Deeley 
  & 
  Parr 
  ... 
  

  

  1913 
  

  

  Deeley 
  & 
  Parr 
  ... 
  

  

  1913 
  

  

  Viscosity. 
  

  

  6-0 
  X 
  10 
  12 
  

  

  84-5 
  X10 
  12 
  

  

  80X10 
  12 
  

  

  17'4 
  xlO 
  12 
  

  

  78-9 
  xlO 
  12 
  

  

  17-5 
  xlO 
  12 
  

  

  1477 
  XlO 
  12 
  

  

  125 
  XlO 
  12 
  

  

  The 
  last 
  two 
  results 
  give 
  the 
  winter 
  viscosity, 
  which 
  is 
  

   probably 
  that 
  for 
  the 
  glacier 
  in 
  an 
  equally 
  dry 
  condition 
  

   from 
  top 
  to 
  bottom, 
  and 
  is 
  based 
  upon 
  the 
  best 
  data 
  so 
  far 
  

   obtained 
  of 
  the 
  velocity 
  and 
  form 
  of 
  a 
  glacier 
  tongue. 
  

  

  The 
  main 
  reasons 
  why 
  our 
  figures 
  for 
  the 
  viscosity 
  are 
  so 
  

   much 
  greater 
  than 
  Weinberg 
  obtained 
  are, 
  that 
  the 
  velocity 
  

   we 
  take 
  is 
  much 
  less, 
  more 
  slip 
  being 
  allowed, 
  our 
  slope 
  for 
  the 
  

   ice 
  is 
  much 
  greater 
  and 
  the 
  viscosity 
  is 
  the 
  winter 
  value. 
  

  

  