﻿228 
  rev. 
  j. 
  p. 
  blake 
  on 
  some 
  [May 
  1897, 
  

  

  at 
  a 
  rough 
  estimate 
  of 
  the 
  average 
  direction 
  and 
  speed. 
  Taking 
  the 
  

   year 
  1895, 
  and 
  treating 
  the 
  records 
  in 
  this 
  way, 
  it 
  appears 
  that 
  the 
  

   air 
  travels 
  at 
  Bhuj, 
  in 
  the 
  various 
  directions, 
  at 
  an 
  average 
  rate 
  of 
  

   10 
  \ 
  miles 
  per 
  hour 
  for 
  the 
  whole 
  year. 
  But 
  at 
  the 
  end 
  of 
  this 
  

   time, 
  the 
  air 
  is 
  not 
  found 
  to 
  have 
  returned 
  upon 
  itself. 
  According 
  

   to 
  the 
  records, 
  a 
  particle 
  of 
  air 
  which 
  travelled 
  constantly 
  with 
  

   the 
  wind 
  would 
  find 
  itself 
  at 
  the 
  end 
  of 
  the 
  year 
  66,000 
  miles 
  

   to 
  the 
  east 
  and 
  9600 
  miles 
  to 
  the 
  north 
  of 
  its 
  initial 
  position. 
  

   These 
  figures, 
  of 
  course, 
  are 
  merely 
  indicative 
  of 
  general 
  results, 
  the 
  

   meaning 
  being 
  that 
  there 
  is, 
  on 
  the 
  whole, 
  a 
  constant 
  passage 
  of 
  air 
  in 
  

   one 
  direction, 
  from 
  a 
  little 
  to 
  the 
  south 
  of 
  west, 
  at 
  a 
  rate 
  of 
  7| 
  miles 
  

   per 
  hour. 
  

  

  We 
  shall 
  form, 
  however, 
  a 
  better 
  idea 
  of 
  the 
  action 
  and 
  power 
  of 
  

   the 
  wind 
  by 
  examining 
  the 
  records 
  in 
  detail. 
  There 
  were, 
  in 
  the 
  first 
  

   place, 
  only 
  40 
  occasions 
  in 
  the 
  year 
  when 
  there 
  was 
  any 
  east 
  in 
  the 
  

   wind 
  at 
  all, 
  and 
  the 
  total 
  velocity 
  of 
  such 
  winds 
  was 
  only 
  12| 
  per 
  

   cent, 
  of 
  that 
  of 
  the 
  westerly 
  winds. 
  Again, 
  for 
  the 
  greater 
  part 
  of 
  the 
  

   year 
  the 
  winds 
  are 
  not 
  excessive, 
  but 
  out 
  of 
  the 
  140 
  days 
  between 
  

   April 
  25th 
  and 
  September 
  11th, 
  no 
  less 
  than 
  90 
  days' 
  gales 
  are 
  

   recorded, 
  7 
  of 
  which 
  are 
  specially 
  recorded 
  as 
  dust-storms. 
  If 
  now 
  

   we 
  confine 
  ourselves 
  to 
  these 
  dates 
  of 
  gale 
  we 
  find 
  that 
  the 
  average 
  

   velocity 
  was 
  20 
  miles 
  per 
  hour, 
  and 
  the 
  average 
  direction 
  about 
  20° 
  

   south 
  of 
  west. 
  The 
  velocity 
  exceeded 
  in 
  six 
  cases 
  30 
  miles 
  per 
  

   hour. 
  This 
  is 
  an 
  average 
  for 
  24 
  hours, 
  and, 
  as 
  gales 
  do 
  not 
  

   continue 
  to 
  have 
  a 
  constant 
  velocity 
  for 
  so 
  long, 
  there 
  must 
  have 
  

   been 
  not 
  infrequent 
  times 
  when 
  the 
  wind 
  was 
  moving 
  at 
  40 
  miles 
  

   per 
  hour. 
  The 
  complete 
  records 
  for 
  other 
  years 
  I 
  have 
  not 
  been 
  able 
  

   to 
  consult, 
  but 
  there 
  is 
  no 
  reason 
  to 
  believe 
  that 
  1895 
  had 
  a 
  maximum 
  

   of 
  wind, 
  nor 
  are 
  we 
  sure 
  that 
  the 
  present 
  winds 
  as 
  a 
  whole 
  are 
  equal 
  

   in 
  intensity 
  to 
  those 
  of 
  some 
  period 
  of 
  the 
  past. 
  We 
  have, 
  therefore, 
  

   good 
  reason 
  to 
  believe 
  that 
  there 
  is 
  adequate 
  force 
  available 
  to 
  do 
  

   the 
  work 
  required. 
  

  

  Moreover, 
  similar 
  work 
  is 
  now 
  being 
  done, 
  as 
  witness 
  the 
  dust- 
  

   storms 
  for 
  which 
  Cutch 
  is 
  famous. 
  As, 
  however, 
  the 
  gales 
  blow 
  

   from 
  the 
  west, 
  it 
  is 
  important 
  to 
  know 
  what 
  happens 
  in 
  that 
  direc- 
  

   tion, 
  and 
  on 
  consulting 
  the 
  Meteorological 
  lieports 
  above 
  quoted 
  

   we 
  find 
  that 
  there 
  were 
  no 
  fewer 
  than 
  55 
  dust-storms 
  recorded 
  at 
  

   Karachi 
  during 
  1895, 
  mostly 
  under 
  westerly 
  winds, 
  and 
  in 
  the 
  other 
  

   stations 
  next 
  north 
  and 
  north-east 
  of 
  Cutch 
  53 
  dust-storms 
  and 
  

   53 
  dust-hazes, 
  which 
  latter 
  may 
  be 
  taken 
  to 
  mean 
  the 
  transport 
  of 
  

   the 
  finer 
  particles 
  of 
  dust. 
  It 
  is 
  obvious, 
  therefore, 
  that 
  the 
  passage 
  

   of 
  fine 
  sand, 
  etc., 
  across 
  the 
  country 
  is 
  a 
  widespread 
  phenomenon. 
  

  

  We 
  have 
  evidence 
  also 
  that 
  the 
  sand 
  thus 
  carried 
  travels 
  with 
  

   great 
  velocity, 
  for, 
  as 
  shown 
  on 
  p. 
  456 
  of 
  the 
  2nd 
  edition 
  (1893) 
  of 
  

   Blauford 
  & 
  Medlicott's 
  ' 
  Geology 
  of 
  India,' 
  there 
  are 
  in 
  Sind 
  two 
  

   types 
  of 
  sandhills 
  — 
  one 
  lying 
  transverse 
  to 
  the 
  prevailing 
  winds 
  and 
  

   the 
  other 
  parallel 
  to 
  them, 
  the 
  direction 
  here 
  being 
  about 
  30° 
  south 
  

   of 
  west. 
  Now 
  it 
  is 
  only 
  necessary 
  to 
  study 
  the 
  drifting 
  of 
  snow 
  to 
  

   see 
  that, 
  while 
  comparatively 
  gentle 
  winds 
  make 
  transverse 
  drift, 
  

   the 
  snow 
  that 
  is 
  borne 
  along 
  tumultuously 
  by 
  the 
  wind 
  lies, 
  when 
  

  

  