﻿JOURNAL 
  

  

  OF 
  THE 
  

  

  WASHINGTON 
  ACADEMY 
  OF 
  SCIENCES 
  

  

  Vol. 
  12 
  June 
  19, 
  1922 
  No. 
  12 
  

  

  OCEANOGRAPHY. 
  — 
  The 
  applications 
  of 
  science 
  and 
  engineering 
  

   in 
  the 
  work 
  of 
  the 
  United 
  States 
  Lighthouse 
  Service.'^ 
  George 
  R. 
  

   Putnam, 
  Lighthouse 
  Service, 
  Department 
  of 
  Commerce. 
  

  

  The 
  Lighthouse 
  Service 
  has 
  a 
  definite 
  function 
  to 
  perform, 
  the 
  pro- 
  

   viding 
  of 
  marks 
  or 
  signals 
  to 
  guide 
  vessels 
  in 
  their 
  proper 
  course 
  and 
  

   to 
  keep 
  them 
  away 
  from 
  danger. 
  In 
  performing 
  this 
  duty 
  it 
  makes 
  

   extensive 
  use 
  of 
  apparatus 
  and 
  appliances 
  developed 
  through 
  scien- 
  

   tific 
  research, 
  and 
  of 
  structures, 
  both 
  on 
  land 
  and 
  afloat, 
  in 
  many 
  cases 
  

   involving 
  difficult 
  engineering 
  problems. 
  The 
  aids, 
  over 
  16,000 
  in 
  

   number, 
  are 
  either 
  on 
  unfixed 
  or 
  floating 
  structures, 
  slightly 
  more 
  than 
  

   half 
  being 
  floating. 
  As 
  to 
  character, 
  they 
  fall 
  into 
  three 
  general 
  groups, 
  

   lights, 
  fog 
  signals, 
  and 
  daymarks, 
  though 
  many 
  aids 
  combine 
  these 
  

   three 
  functions 
  or 
  two 
  of 
  them. 
  

  

  Lighthouses 
  and 
  other 
  lighted 
  aids. 
  — 
  Though 
  in 
  many 
  respects 
  the 
  

   fog 
  signals 
  are 
  the 
  aids 
  most 
  needed 
  by 
  the 
  mariner, 
  yet 
  the 
  lights 
  

   are 
  the 
  more 
  numerous 
  and 
  more 
  widely 
  known 
  marks, 
  and 
  their 
  de- 
  

   velopment 
  will 
  be 
  first 
  described. 
  

  

  The 
  outermost 
  lights 
  are 
  those 
  of 
  the 
  outside 
  lightships, 
  which 
  are 
  

   in 
  effect 
  floating 
  lighthouses 
  anchored 
  off 
  the 
  coast 
  and 
  in 
  the 
  ap- 
  

   proaches 
  to 
  the 
  great 
  seaports. 
  These 
  are 
  few 
  in 
  number, 
  only 
  22 
  

   for 
  the 
  Atlantic, 
  Gulf 
  and 
  Pacific 
  coasts, 
  but 
  they 
  are 
  the 
  guides 
  most 
  

   used 
  by 
  the 
  larger 
  class 
  of 
  vessels, 
  as 
  they 
  can 
  run 
  directly 
  for 
  these 
  

   lightships 
  without 
  risk 
  of 
  stranding 
  if 
  somewhat 
  off 
  in 
  reckoning. 
  An 
  

   example 
  is 
  the 
  Nantucket 
  light 
  vessel, 
  anchored 
  41 
  miles 
  off 
  the 
  land; 
  

   this 
  is 
  the 
  mark 
  for 
  which 
  most 
  of 
  the 
  vessels 
  crossing 
  the 
  north 
  At- 
  

   lantic 
  direct 
  their 
  course 
  westward 
  bound. 
  There 
  are 
  now 
  also 
  a 
  num- 
  

   ber 
  of 
  large 
  sea 
  gas 
  buoys 
  anchored 
  off 
  the 
  coast 
  and 
  entrances. 
  

  

  The 
  primary 
  coast 
  lights 
  are 
  the 
  principal 
  lighthouses 
  marking 
  prom- 
  

   inent 
  headlands, 
  offlying 
  islands 
  and 
  rocks, 
  important 
  entrances, 
  and 
  

   some 
  intermediate 
  points. 
  On 
  a 
  well 
  lighted 
  coast 
  these 
  primary 
  

  

  1 
  Address 
  delivered 
  at 
  the 
  Bureau 
  of 
  vStandards, 
  May 
  5, 
  1922. 
  Received 
  May 
  15, 
  1922. 
  

  

  279 
  

  

  