﻿146 
  Scientific 
  Intelligence. 
  

  

  were 
  buried 
  to 
  great 
  depths, 
  folded 
  and 
  metamorphosed. 
  This 
  

   metamorphism 
  was 
  to 
  a 
  large 
  degree 
  contemporaneous 
  with 
  an 
  

   intrusion 
  of 
  a 
  great 
  mass 
  of 
  granite 
  and 
  the 
  injection 
  of 
  granite 
  

   and 
  pegmatite 
  into 
  the 
  sediments. 
  Later 
  erosion 
  exposed 
  these 
  

   rocks 
  and 
  then 
  another 
  subsidence 
  occurred 
  and 
  Paleozoic 
  sedi- 
  

   ments 
  were 
  deposited 
  upon 
  them. 
  These 
  latter 
  have 
  since 
  been 
  

   largely 
  removed 
  by 
  erosion 
  and 
  the 
  Precambrian 
  rocks 
  again 
  

   exposed. 
  The 
  metamorphism 
  of 
  the 
  limestone 
  produced 
  a 
  crys- 
  

   talline 
  rock 
  contained 
  diopside 
  and 
  tremolite, 
  which 
  subsequently 
  

   have 
  been 
  largely 
  altered 
  into 
  serpentine 
  and 
  talc. 
  The 
  sul- 
  

   phides, 
  chiefly 
  pyrite 
  and 
  sphalerite 
  with 
  only 
  a 
  little 
  galena, 
  

   were 
  deposited 
  during 
  the 
  period 
  of 
  metamorphism. 
  They 
  were 
  

   formed 
  after 
  the 
  diopside 
  and 
  tremolite 
  but 
  mostly 
  preceding 
  

   the 
  change 
  of 
  the 
  latter 
  minerals 
  to 
  talc 
  and 
  serpentine. 
  The 
  

   ore 
  minerals 
  were 
  apparently 
  deposited 
  by 
  replacement 
  action 
  

   effected 
  through 
  the 
  influence 
  of 
  hot 
  gases 
  and 
  solutions 
  evolved 
  

   by 
  the 
  intruded 
  granitic 
  magma. 
  w. 
  e. 
  f. 
  

  

  III. 
  Miscellaneous 
  Scientific 
  Intelligence. 
  

  

  1. 
  Report 
  of 
  the 
  Secretary 
  of 
  the 
  Smithsonian 
  Institution, 
  

   Charles 
  D. 
  Walcott, 
  for 
  the 
  year 
  ending 
  June 
  30, 
  1918. 
  Pp. 
  

   101. 
  Washington, 
  1918. 
  — 
  The 
  work 
  of 
  the 
  Institution 
  during 
  

   the 
  past 
  year 
  has 
  been 
  largely 
  modified 
  by 
  the 
  special 
  war 
  condi- 
  

   tions 
  existing 
  in 
  "Washington. 
  These 
  have 
  affected 
  the 
  labors 
  

   of 
  the 
  staff, 
  and 
  particularly 
  of 
  the 
  Secretary 
  in 
  connection 
  with 
  

   the 
  National 
  Research 
  Council. 
  It 
  is 
  also 
  to 
  be 
  noted 
  that 
  the 
  

   War 
  Department 
  allotted 
  the 
  sum 
  of 
  ten 
  thousand 
  dollars 
  for 
  

   experimental 
  work 
  in 
  aviation 
  in 
  connection 
  with 
  the 
  Signal 
  

   Corps. 
  Several 
  bequests 
  are 
  mentioned 
  in 
  the 
  report 
  and 
  also 
  

   the 
  gift 
  by 
  Dr. 
  Frank 
  Springer 
  of 
  his 
  collection 
  of 
  fossil 
  crinoids 
  

   and 
  related 
  groups 
  of 
  Echinoderms. 
  A 
  fund 
  of 
  thirty 
  thousand 
  

   dollars 
  has 
  been 
  arranged 
  for 
  to 
  be 
  devoted 
  to 
  the 
  care 
  of 
  the 
  

   collection. 
  Various 
  researches 
  and 
  explorations 
  are 
  noted, 
  but 
  

   these 
  also 
  have 
  been 
  much 
  limited 
  by 
  the 
  war. 
  The 
  Institution 
  

   has 
  met 
  with 
  a 
  very 
  serious 
  loss 
  in 
  the 
  death 
  of 
  Dr. 
  Rathbun. 
  

   already 
  mentioned 
  in 
  these 
  pages 
  (see 
  vol. 
  46, 
  p. 
  620, 
  pp. 
  720- 
  

   763). 
  Among 
  the 
  various 
  appendices 
  to 
  the 
  report 
  of 
  the 
  

   Secretary, 
  that 
  on 
  the 
  II. 
  S. 
  National 
  Museum 
  has 
  been 
  prepared 
  

   by 
  W. 
  deC. 
  Ravenel; 
  the 
  other 
  chapters 
  in 
  this 
  part 
  of 
  the 
  

   report 
  detail 
  the 
  special 
  activities 
  of 
  the 
  Institution; 
  among 
  

   these 
  the 
  National 
  Zoological 
  Park, 
  and 
  also 
  the 
  Astrophysical 
  

   Observatory 
  deserve 
  special 
  attention. 
  The 
  work 
  of 
  the 
  Obser- 
  

   vatory 
  is 
  summarized 
  by 
  Dr. 
  C. 
  G. 
  Abbot 
  in 
  the 
  following 
  para- 
  

   graph 
  : 
  ' 
  ' 
  During 
  the 
  year 
  covered 
  by 
  this 
  report, 
  great 
  advance 
  

   has 
  been 
  made 
  in 
  the 
  study 
  of 
  very 
  long 
  wave-length 
  rays 
  and 
  

   their 
  transmissibility 
  in 
  our 
  atmosphere. 
  Solar 
  constant 
  work 
  

   at 
  Mount 
  Wilson 
  has 
  been 
  continued 
  and 
  improved. 
  An 
  

   expedition 
  under 
  the 
  auspices 
  of 
  the 
  Hodgkins 
  Fund 
  of 
  the 
  

  

  