﻿[29] 
  REPORT 
  ON 
  THERMOMETERS. 
  213 
  

  

  ive 
  shield 
  to 
  the 
  bulb 
  of 
  the. 
  Miller- 
  Oa 
  sella 
  thermometer, 
  its 
  only 
  impor- 
  

   tant 
  distinction 
  from 
  Sixc's 
  form 
  of 
  a 
  century 
  ago, 
  was 
  certainly 
  tried 
  by 
  

   Sir 
  Edward 
  Sabine 
  as 
  early 
  as 
  1822 
  (see 
  p. 
  [141), 
  an 
  ^ 
  thought 
  of 
  by 
  Peron* 
  

   about 
  1804. 
  Aime 
  suggested 
  and 
  appears 
  to 
  have 
  used 
  an 
  outer 
  glass 
  

   case, 
  sealed 
  by 
  the 
  blowpipe, 
  some, 
  time 
  before 
  1845, 
  t 
  and 
  the 
  same 
  de- 
  

   vice 
  for 
  meeting 
  and 
  avoiding 
  the 
  pressure 
  error 
  at 
  great 
  depths 
  was 
  

   made 
  public 
  property 
  by 
  Sir 
  William 
  Thomson's 
  well-known 
  paper 
  upon 
  

   the 
  effect 
  of 
  pressure 
  upon 
  the 
  freezing-point 
  of 
  liquids 
  in 
  1850. 
  Aime 
  

   also 
  used 
  messengers 
  for 
  detaching 
  weights 
  and 
  for 
  oversetting 
  self- 
  

   registering 
  thermometers 
  prior 
  to 
  1845 
  (op. 
  cit., 
  p. 
  5), 
  and 
  devised 
  sev- 
  

   eral 
  different 
  patterns 
  of 
  thermometers 
  for 
  registering 
  deep-sea 
  temper- 
  

   atures 
  by 
  being 
  overset 
  at 
  the 
  depth 
  to 
  be 
  investigated, 
  which, 
  when 
  

   protected 
  by 
  his 
  closed 
  glass 
  or 
  metal 
  tubes, 
  gave 
  excellent 
  results. 
  

   The 
  propeller 
  was 
  used 
  by 
  Messrs. 
  ftcgrctti 
  and 
  Zambra 
  in 
  1874 
  to 
  reverse 
  

   their 
  earlier 
  form 
  of 
  thermometer, 
  and 
  the 
  same 
  firm, 
  as 
  has 
  been 
  ex- 
  

   plained, 
  preceded 
  Dr. 
  Miller 
  by 
  about 
  twelve 
  years 
  in 
  the 
  application 
  of 
  

   a 
  protecting 
  shield 
  to 
  Sixe's 
  self-registering 
  thermometer. 
  

  

  The 
  first 
  practical 
  self-registering 
  thermometers 
  appear 
  to 
  have 
  been 
  

   the 
  inventions 
  of 
  Lord 
  Charles 
  Cavendish 
  in 
  1757, 
  registering 
  by 
  the 
  

   measurement 
  of 
  a 
  portion 
  of 
  fluid 
  which 
  had 
  been 
  caused 
  to 
  overflow 
  at 
  

   the 
  maximum 
  or 
  minimum 
  temperature 
  encountered 
  by 
  the 
  instru- 
  

   ment. 
  Mr. 
  Sixe, 
  who 
  expressly 
  acknowledges 
  his 
  obligations 
  to 
  these 
  

   inventions, 
  improved 
  them 
  in 
  form 
  and 
  by 
  the 
  addition 
  of 
  a 
  movable- 
  

   steel 
  index. 
  The 
  idea 
  of 
  protection 
  against 
  pressure 
  by 
  an 
  outer 
  

   shield 
  first 
  appears 
  about 
  the 
  beginning 
  of 
  this 
  century 
  and 
  was 
  prac- 
  

   tically 
  perfected 
  about 
  1845, 
  as 
  early 
  as 
  which 
  date 
  messengers 
  were 
  in 
  

   use 
  for 
  detaching 
  weights, 
  for 
  closing 
  water 
  bottles, 
  and 
  for 
  oversetting 
  

   thermometers. 
  Revolving 
  propellers 
  have 
  been 
  used, 
  abandoned, 
  and 
  

   taken 
  up 
  again 
  in 
  very 
  recent 
  times, 
  and 
  the 
  latest 
  novelty 
  appears 
  

   in 
  the 
  modern 
  JSTegretti-Zambra 
  thermometer, 
  in 
  the 
  use 
  of 
  the 
  same 
  

   fluid 
  for 
  the 
  measurement 
  and 
  the 
  registration 
  of 
  temperature, 
  and 
  in 
  

   breaking 
  the 
  column, 
  when 
  overset, 
  by 
  means 
  of 
  a 
  peculiar 
  narrowing 
  

   of 
  the 
  tube 
  at 
  a 
  particular 
  place. 
  From 
  the 
  time 
  of 
  Lord 
  Cavendish 
  

   to 
  the 
  present 
  the 
  progress 
  of 
  improvements 
  in 
  the 
  form 
  of 
  deep-sea 
  

   thermometers 
  has 
  been 
  by 
  a 
  very 
  natural 
  and 
  regular 
  process 
  of 
  evolu- 
  

   tion 
  and 
  of 
  survival 
  (or 
  sometimes 
  revival) 
  of 
  the 
  variations 
  best 
  suited 
  

   to 
  their 
  purpose. 
  

  

  Central 
  Station, 
  Wood's 
  LToll, 
  Mass., 
  July 
  31, 
  1885. 
  

  

  * 
  Voyage 
  tie 
  Decouvprtes 
  anx 
  Tones 
  Australes. 
  Vol. 
  II, 
  Paris, 
  1816, 
  p. 
  330, 
  note. 
  

   t 
  Arm. 
  de 
  Ohimie 
  et 
  de 
  Physique, 
  Ser. 
  3, 
  t. 
  xv, 
  p. 
  10, 
  1845. 
  

  

  