﻿REPORT 
  OF 
  THE 
  SECRETARY 
  XI 
  

  

  INTERNATIONAL 
  EXCHANGE 
  SERVICE 
  

  

  Secretary 
  (in 
  charge). 
  — 
  Charles 
  G. 
  Abbot. 
  

   Acting 
  Chief 
  Clerk.— 
  F. 
  E. 
  Gass. 
  

  

  NATIONAL 
  ZOOLOGICAL 
  PARK 
  

  

  Director. 
  — 
  William 
  M. 
  Mann. 
  

   Assistant 
  Director. 
  — 
  Ebnest 
  P. 
  Walker. 
  

  

  ASTROPHYSICAL 
  OBSERVATORY 
  

  

  Director. 
  — 
  Charles 
  G. 
  Abbot. 
  

  

  Division 
  of 
  Astrophysical 
  Research 
  : 
  Loyal 
  B. 
  Aldrich, 
  assistant 
  director 
  ; 
  

   William 
  H. 
  Hoover, 
  senior 
  astrophysicist. 
  

  

  Division 
  of 
  Radiation 
  and 
  Organisms: 
  Earl 
  S. 
  Johnston, 
  assistant 
  director; 
  

   Edward 
  D. 
  McAlister, 
  senior 
  physicist; 
  Leland 
  B. 
  Clark, 
  engineer 
  (precision 
  

   instruments) 
  ; 
  Robert 
  L. 
  Weintraub, 
  associate 
  biochemist. 
  

  

  