﻿F. 
  A. 
  Ferret 
  — 
  Volcanic 
  Research 
  at 
  Kilauea. 
  479 
  

  

  will 
  be 
  seen 
  later, 
  tubes 
  of 
  nickel, 
  the 
  fusion 
  point 
  of 
  which 
  we 
  

   may 
  take 
  as 
  being 
  at 
  the 
  least 
  1450° 
  C, 
  were 
  readily 
  dissolved 
  

   in 
  this 
  lava, 
  whose 
  temperature 
  could 
  not 
  have 
  approached 
  to 
  

   within 
  300° 
  of 
  this. 
  

  

  The 
  first 
  attempts 
  to 
  obtain 
  a 
  temperature 
  measurement 
  were 
  

   made 
  with 
  resistance 
  coils 
  of 
  fine 
  platinum 
  wire 
  enclosed 
  for 
  

   protection 
  in 
  concentrically 
  disposed 
  tubes 
  of 
  quartz, 
  nickel 
  

   and 
  iron, 
  the 
  electrical 
  resistance 
  of 
  the 
  platinum 
  coil 
  varying 
  

   with 
  its 
  temperature 
  and 
  being 
  read 
  by 
  suitable 
  instruments 
  

   connected 
  with 
  the 
  shore 
  end 
  of 
  the 
  connecting 
  cable. 
  Need- 
  

   less 
  to 
  say, 
  the 
  metal 
  tubes 
  were 
  several 
  meters 
  in 
  length, 
  and 
  

   the 
  adjoining 
  portion 
  of 
  the 
  insulated 
  cable 
  was 
  protected 
  by 
  

   a 
  spiral 
  steel 
  casing. 
  

  

  One 
  of 
  these 
  instruments 
  was 
  successfully 
  lowered 
  into 
  the 
  

   lake 
  on 
  July 
  20th, 
  but 
  the 
  electrical 
  connection 
  failed 
  at 
  the 
  

   moment 
  of 
  immersion 
  and 
  a 
  lava 
  fountain 
  carried 
  away 
  the 
  

   instrument 
  with 
  all 
  the 
  armored 
  cable. 
  Just 
  before 
  this 
  oc- 
  

   curred, 
  however, 
  the 
  spring 
  of 
  the 
  main 
  cable 
  had 
  lifted 
  the 
  

   instrument, 
  for 
  a 
  moment, 
  quite 
  clear 
  of 
  the 
  lake 
  and 
  it 
  was 
  

   seen 
  that 
  the 
  metal 
  tube 
  had 
  been 
  fused 
  off 
  at 
  the 
  level 
  of 
  

   immersion. 
  

  

  Nine 
  days 
  later 
  a 
  second, 
  similar 
  instrument 
  failed, 
  in 
  like 
  

   manner, 
  to 
  register, 
  and 
  it 
  was 
  evident 
  that 
  this 
  type 
  of 
  ther- 
  

   mometer, 
  however 
  useful 
  in 
  the 
  laboratory, 
  was 
  too 
  delicate 
  

   for 
  the 
  rough 
  conditions 
  of 
  crater 
  activity.* 
  

  

  The 
  third 
  and 
  successful 
  attempt 
  was 
  made 
  on 
  July 
  31st 
  

   with 
  a 
  thermo-electrio 
  couple 
  of 
  platinum 
  and 
  iridio-platinum. 
  

   This 
  was 
  set 
  up 
  by 
  Dr. 
  Shepherd 
  in 
  a 
  heavy 
  iron 
  tube 
  and 
  the 
  

   cold 
  end 
  of 
  the 
  element 
  was 
  surrounded 
  by 
  a 
  large 
  iron 
  cylin- 
  

   der 
  filled 
  with 
  water. 
  

  

  It 
  should 
  be 
  said 
  here 
  that, 
  by 
  this 
  time, 
  the 
  conditions 
  at 
  

   the 
  crater 
  had 
  become 
  exceedingly 
  unfavorable 
  for 
  the 
  contin- 
  

   uation 
  of 
  the 
  experiments. 
  The 
  sinking 
  of 
  the 
  lake 
  greatly 
  

   increased 
  the 
  difficulty 
  of 
  lowering 
  the 
  instruments 
  into 
  contact 
  

   with 
  the 
  lava, 
  while 
  dense 
  clouds 
  of 
  vapor 
  rendered 
  the 
  lake 
  

   itself 
  quite 
  invisible 
  from 
  the 
  operating 
  point 
  and 
  made 
  neces- 
  

   sary 
  a 
  line 
  of 
  signal-men 
  around 
  each 
  side 
  of 
  the 
  crater 
  for 
  

   receiving 
  and 
  transmitting 
  previously 
  arranged 
  wig-wag 
  signals 
  

   from 
  the 
  writer, 
  to 
  whom, 
  alone 
  — 
  perched 
  upon 
  the 
  crag 
  of 
  a 
  

   sunken 
  ledge, 
  mside 
  the 
  pit 
  — 
  the 
  lake 
  surface 
  and 
  the 
  descend- 
  

   ing 
  instrument 
  were 
  visible. 
  

  

  In 
  this 
  manner 
  the 
  element 
  was 
  immersed 
  some 
  30 
  to 
  50 
  cm 
  

   below 
  the 
  surface 
  of 
  the 
  lava, 
  where 
  a 
  thin 
  crust 
  was 
  readily 
  

   perforated 
  by 
  the 
  descending 
  tube. 
  The 
  shore 
  instrument 
  

   showed 
  the 
  increasing 
  temperature 
  as 
  the 
  element 
  descended 
  

  

  * 
  The 
  Kilauea 
  lava 
  fountains 
  send 
  tons 
  of 
  heavy 
  liquid 
  to 
  a 
  height 
  of 
  from 
  

   6 
  to 
  12 
  meters. 
  

  

  