﻿220 
  ANNUAL 
  REPORT 
  SMITHSONIAN 
  INSTITUTION, 
  1922 
  

  

  splotches 
  among 
  the 
  cirro-cumuli, 
  or 
  other 
  high 
  type, 
  and 
  borders 
  

   of 
  thin 
  lenticular 
  alto-strati 
  and 
  alto-cumuli, 
  of 
  gorgeous 
  opalescent 
  

   rose 
  pinks, 
  emerald 
  greens, 
  and 
  other 
  colors, 
  randomly 
  mixed 
  and 
  

   covering 
  a 
  large 
  part 
  of 
  the 
  sky 
  15° 
  to 
  30° 
  from 
  the 
  sun. 
  

  

  It 
  can 
  be 
  fully 
  explained 
  (being 
  only 
  fragments 
  of 
  giant 
  coronas 
  

   due 
  to 
  unusually 
  small 
  droplets), 
  but 
  only 
  in 
  the 
  language 
  of 
  the 
  

   physicist 
  and 
  symbols 
  of 
  the 
  mathematician. 
  Its 
  beauty, 
  however, 
  

   can 
  be 
  enjoyed 
  by 
  all, 
  and 
  whoever 
  looks 
  at 
  the 
  heavens 
  for 
  anything 
  

   should 
  watch 
  most 
  frequently 
  and 
  carefully 
  for 
  the 
  glorious 
  appari- 
  

   tion 
  of 
  the 
  iridescent 
  cloud. 
  

  

  CLOUDS 
  AS 
  WEATHER 
  SIGNS. 
  

  

  Since 
  the 
  height, 
  extent, 
  and 
  shape 
  of 
  clouds 
  depend 
  upon 
  the 
  

   humidity, 
  temperature, 
  and 
  motion 
  of 
  the 
  atmosphere, 
  it 
  is 
  obvious 
  

   that 
  they 
  often 
  may 
  furnish 
  helpful 
  hints 
  of 
  the 
  coming 
  weather. 
  

   Thus, 
  thin 
  cirrus 
  clouds, 
  when 
  not 
  increasing 
  in 
  extent 
  nor 
  growing 
  

   denser, 
  indicate 
  fair 
  weather 
  for 
  at 
  least 
  24 
  hours; 
  and 
  the 
  same 
  is 
  

   true 
  of 
  the 
  alto-cumuli. 
  In 
  general 
  

  

  " 
  The 
  higher 
  the 
  clouds, 
  the 
  finer 
  the 
  weather." 
  

  

  On 
  the 
  other 
  hand, 
  when 
  the 
  cirrus 
  grows 
  denser, 
  and 
  when 
  the 
  

   sky 
  is 
  covered 
  with 
  cirro-cumuli, 
  rain 
  within 
  24 
  hours 
  is 
  likely. 
  

  

  " 
  Mackerel 
  scales 
  and 
  mares' 
  tails 
  

   Make 
  lofty 
  ships 
  carry 
  low 
  sails." 
  

  

  Also, 
  when 
  large 
  cumuli 
  develop 
  in 
  the 
  forenoon, 
  there 
  probably 
  

   will 
  be 
  local 
  thundershowers 
  in 
  the 
  afternoon. 
  

  

  " 
  In 
  the 
  morning 
  mountains, 
  

   In 
  the 
  evening 
  fountains." 
  

  

  Again, 
  when 
  two 
  or 
  more 
  layers 
  of 
  cloud 
  are 
  moving 
  in 
  different 
  

   directions, 
  foul 
  weather 
  is 
  almost 
  certain 
  to 
  occur 
  very 
  soon. 
  In 
  

   short, 
  if 
  one 
  may 
  coin 
  a 
  " 
  proverb," 
  

  

  Whene'er 
  the 
  clouds 
  do 
  weave 
  

   'Twill 
  storm 
  hefore 
  they 
  leave. 
  

  

  Clouds 
  of 
  the 
  lower 
  and 
  intermediate 
  levels 
  from 
  north 
  to 
  west 
  

   usually 
  imply 
  fair 
  weather 
  for 
  a 
  day 
  or 
  two; 
  clouds 
  from 
  east 
  to 
  

   south 
  generally 
  mean 
  rain 
  within 
  24 
  hours. 
  (This 
  is 
  for 
  most 
  of 
  the 
  

   temperate 
  regions 
  of 
  the 
  Northern 
  Hemisphere; 
  for 
  the 
  Southern 
  

   Hemisphere, 
  write 
  north 
  for 
  south 
  and 
  south 
  for 
  north.) 
  

  

  " 
  When 
  the 
  carry 
  [current 
  of 
  clouds] 
  goes 
  west, 
  

   Gude 
  weather 
  is 
  past 
  ; 
  

   When 
  the 
  carry 
  goes 
  east 
  

   Gude 
  weather 
  comes 
  nest." 
  

  

  