﻿416 
  Resistance 
  due 
  to 
  Obliquely 
  Moving 
  Waves, 
  

  

  observation 
  of 
  the 
  wave-system 
  and 
  resistance 
  to 
  add 
  and 
  

   remove 
  material 
  at 
  and 
  mider 
  the 
  places 
  indicated 
  (see 
  

   figure), 
  and 
  then 
  after 
  each 
  moderate 
  change 
  to 
  redetermine 
  

  

  ABC 
  is 
  the 
  original 
  form 
  of 
  one 
  side 
  of 
  tlie 
  ship 
  ; 
  ADEF 
  the 
  wave- 
  

   profile, 
  D 
  and 
  F 
  being 
  elevations 
  and 
  E 
  a 
  depression. 
  The 
  dotted 
  

   line 
  then 
  indicates 
  the 
  direction 
  of 
  the 
  proposed 
  alterations. 
  

  

  the 
  form 
  of 
  the 
  waves 
  and 
  the 
  force 
  of 
  resistance. 
  It 
  is 
  

   possible 
  of 
  course 
  that 
  experiments 
  in 
  this 
  direction 
  with 
  

   discouraging 
  results 
  have 
  been 
  made 
  already, 
  but 
  I 
  have 
  seen 
  

   no 
  suggestion 
  of 
  them 
  ; 
  and 
  it 
  may 
  be 
  that 
  the 
  prepossessions 
  

   of 
  naval 
  architects 
  would 
  be 
  too 
  unfavourable 
  to 
  allow 
  such 
  

   an 
  idea 
  to 
  be 
  entertained. 
  

  

  One 
  or 
  two 
  questions 
  are 
  touched 
  upon 
  in 
  conclusion. 
  It 
  

   may 
  be 
  asked 
  how 
  far 
  above 
  and 
  below 
  the 
  normal 
  water 
  

   level 
  should 
  the 
  undulating 
  form 
  be 
  carried? 
  Observations 
  

   of 
  the 
  actual 
  pressures 
  at 
  various 
  points 
  with 
  suitable 
  gauges 
  

   would 
  be 
  the 
  best 
  guide, 
  but 
  in 
  general 
  the 
  variation 
  of 
  

   pressure 
  due 
  to 
  waves 
  does 
  not 
  extend 
  far 
  down 
  in 
  comparison 
  

   with 
  the 
  wave-length. 
  But 
  here 
  it 
  is 
  to 
  be 
  remembered 
  that 
  

   most 
  actual 
  ships 
  are 
  exposed 
  to 
  variations 
  of 
  loading 
  and 
  to 
  

   encounters 
  with 
  long 
  waves 
  originating 
  in 
  wind. 
  Another 
  

   thing 
  that 
  might 
  have 
  to 
  be 
  borne 
  in 
  mind 
  is 
  the 
  danger 
  of 
  

   eddy 
  making 
  if 
  the 
  undulations 
  o£ 
  form 
  were 
  made 
  too 
  pro- 
  

   nounced, 
  but 
  this 
  consideration 
  can 
  hardly 
  be 
  prohibitive 
  of 
  

   a 
  moderate 
  application 
  of 
  the 
  principle. 
  Again, 
  it 
  may 
  be 
  

   noted 
  that 
  strictly 
  speaking 
  the 
  wave-system 
  is 
  a 
  function 
  of 
  

   the 
  speed, 
  so 
  that 
  the 
  adjustment 
  could 
  be 
  complete 
  only 
  for 
  

   a 
  single 
  speed. 
  But 
  this 
  objection 
  does 
  not 
  seem 
  very 
  serious. 
  

   To 
  discuss 
  these 
  questions 
  further 
  at 
  the 
  present 
  stage 
  would 
  

   be 
  premature. 
  

  

  Terling 
  Place, 
  Witham. 
  

  

  