﻿APPENDIX 
  7 
  

  

  EEPORT 
  ON 
  THE 
  ASTROPHYSICAL 
  OBSERVATORY 
  

  

  Sir 
  : 
  The 
  Astropli3^sical 
  Observatory 
  was 
  conducted 
  under 
  the 
  fol- 
  

   lowing 
  passage 
  of 
  the 
  independent 
  offices 
  appropriation 
  act 
  approved 
  

   April 
  22, 
  1926 
  : 
  

  

  Astropbysical 
  Observatory 
  : 
  For 
  maintenance 
  of 
  the 
  Astrophysical 
  Observa- 
  

   tory, 
  under 
  the 
  direction 
  of 
  the 
  Smithsonian 
  Institution, 
  including 
  assistants, 
  

   purchase 
  of 
  books, 
  periodicals, 
  and 
  apparatus, 
  making 
  necessary 
  observations 
  

   in 
  high 
  altitudes, 
  repairs 
  and 
  alterations 
  of 
  buildings, 
  preparation 
  of 
  manu- 
  

   scripts, 
  drawings, 
  and 
  illustrations, 
  traveling 
  expenses, 
  and 
  miscellaneous 
  

   expenses, 
  $31,180, 
  of 
  which 
  nmount 
  not 
  to 
  exceed 
  $27,840 
  may 
  be 
  expended 
  

   for 
  personal 
  services 
  in 
  the 
  District 
  of 
  Columbia. 
  

  

  The 
  observatory 
  occupies 
  a 
  number 
  of 
  frame 
  structures 
  within 
  an 
  

   inclosure 
  of 
  about 
  16,000 
  square 
  feet 
  south 
  of 
  the 
  Smithsonian 
  

   administration 
  building 
  at 
  Washington, 
  a 
  cement 
  observing 
  station 
  

   and 
  frame 
  structure 
  for 
  observers 
  on 
  a 
  plot 
  of 
  10,000 
  square 
  feet 
  

   leased 
  from 
  the 
  Mount 
  Wilson 
  Observatory, 
  and 
  an 
  observing 
  station 
  

   on 
  Table 
  Mountain, 
  Calif. 
  This 
  last 
  station, 
  provided 
  by 
  Mr. 
  John 
  A, 
  

   Roebling, 
  includes 
  a 
  tunnel 
  for 
  instruments, 
  small 
  structures 
  for 
  the 
  

   field 
  director 
  and 
  for 
  the 
  assistant, 
  a 
  shop, 
  and 
  a 
  garage. 
  

  

  The 
  Astroph^'sical 
  Observatory 
  also 
  defrays 
  a 
  part 
  of 
  the 
  cost 
  of 
  

   the 
  maintenance 
  of 
  the 
  observing 
  station 
  at 
  Montezuma, 
  Chile, 
  which 
  

   was 
  erected 
  in 
  1920, 
  with 
  means 
  furnished 
  by 
  Mr. 
  Roebling. 
  The 
  

   constructions 
  there 
  comprise 
  a 
  tunnel 
  for 
  instruments, 
  a 
  small 
  struc- 
  

   ture 
  for 
  observers, 
  shop, 
  garage, 
  and 
  a 
  telephone 
  line 
  12 
  miles 
  to 
  

   Calama. 
  

  

  The 
  present 
  value 
  of 
  the 
  buildings 
  and 
  equipment 
  for 
  the 
  Astro- 
  

   physical 
  Observatory 
  owned 
  by 
  the 
  Government 
  is 
  .estimated 
  at 
  

   §50,000. 
  This 
  estimate 
  contemplates 
  the 
  cost 
  required 
  to 
  replace 
  

   the 
  outfit 
  for 
  the 
  purposes 
  of 
  the 
  investigations. 
  

  

  WORK 
  AT 
  WASHINGTON 
  

  

  (a) 
  Radiometer. 
  — 
  With 
  the 
  cooperation 
  of 
  the 
  Bureau 
  of 
  Stand- 
  

   ards, 
  whose 
  glass 
  blower, 
  Mr. 
  Sperling, 
  made 
  the 
  difficult 
  glass 
  

   work 
  needed 
  with 
  glass-sealed 
  optical 
  windows, 
  preparations 
  were 
  

   made 
  to 
  construct 
  a 
  very 
  sensitive 
  radiometer. 
  It 
  will 
  be 
  recalled 
  

   that 
  in 
  October, 
  1923, 
  Dr. 
  C. 
  G. 
  Abbot 
  employed 
  a 
  radiometer 
  

   prepared 
  by 
  Nichols 
  and 
  Tear, 
  and, 
  observing 
  with 
  the 
  100-inch 
  

   telescope 
  on 
  Mount 
  Wilson, 
  obtained 
  the 
  first 
  energy-spectra 
  of 
  

   stars 
  ever 
  measured 
  with 
  heat-recording 
  apparatus. 
  In 
  1924 
  he 
  

  

  109 
  

  

  