﻿180 
  

  

  liolborn 
  and 
  Day 
  — 
  Gas 
  Thermometer 
  at 
  

  

  of 
  the 
  difficulty 
  in 
  packing 
  tliera 
  so 
  as 
  to 
  prevent 
  the 
  vapor 
  

   from 
  escaping, 
  consequently 
  they 
  v^ere 
  enclosed 
  in 
  a 
  sheet 
  iron 
  

   cylinder 
  made 
  fast 
  to 
  the 
  cover 
  of 
  the 
  kettle. 
  Around 
  the 
  

   outside 
  of 
  this 
  cylinder 
  the 
  vapor 
  circulated 
  freely 
  and 
  took 
  

   fire 
  on 
  coming 
  in 
  contact 
  with 
  the 
  air 
  at 
  the 
  end 
  of 
  the 
  tube 
  R. 
  

   Table 
  y 
  contains 
  the 
  results 
  of 
  two 
  trials 
  with 
  bulb 
  No. 
  II 
  

   in 
  this 
  kettle. 
  

  

  Table 
  V. 
  

  

  Bulb 
  (No. 
  II). 
  — 
  Berlin 
  porcelain 
  glazed 
  inside 
  and 
  out. 
  Gas 
  — 
  Nitrogen. 
  

  

  y. 
  = 
  10ri36=«'". 
  ^,= 
  2-837. 
  3/3 
  = 
  0-0000132. 
  

  

  After 
  filling. 
  

  

  Ho 
  

  

  a 
  

  

  t 
  

  

  Ci 
  

  

  Obs.-Calcu 
  

  

  1st 
  day 
  

  

  415-40 
  

  

  0-003669 
  

  

  

  

  

  3d 
  " 
  

  

  

  

  Heated 
  to 
  700°. 
  

  

  

  

  4th 
  " 
  

  

  415-80 
  

  

  

  

  

  

  4th 
  " 
  

  

  

  

  8()4'2° 
  

  

  7219 
  

  

  -7-4° 
  

  

  

  

  

  906 
  

  

  8293 
  

  

  — 
  4-2 
  

  

  

  

  

  920-3 
  

  

  8415 
  

  

  -1-0 
  

  

  

  

  

  933-7 
  

  

  8564 
  

  

  -1-0 
  

  

  5th 
  " 
  

  

  417-05 
  

  

  0-003669 
  

  

  

  

  

  '7th 
  " 
  

  

  

  

  909-4 
  

  

  8304 
  

  

  -1-8 
  

  

  

  

  

  914-8 
  

  

  8351 
  

  

  ^0-7 
  

  

  

  

  

  915-4 
  

  

  8354 
  

  

  -0-4 
  

  

  

  

  

  916-6 
  

  

  8367 
  

  

  -0-3 
  

  

  

  

  

  917-5 
  

  

  8373 
  

  

  . 
  0-0 
  

  

  

  

  

  918-3 
  

  

  8382 
  

  

  0-0 
  

  

  

  

  

  918-9 
  

  

  8387 
  

  

  + 
  0-1 
  

  

  

  

  

  919-4 
  

  

  8392 
  

  

  4-0-2 
  

  

  

  

  

  920-0 
  

  

  8393 
  

  

  + 
  0-7 
  

  

  

  

  

  920-4 
  

  

  8398 
  

  

  + 
  0-7 
  

  

  8th 
  '' 
  

  

  417-29 
  

  

  0-003671 
  

  

  

  

  

  An 
  agreement 
  between 
  observed 
  and 
  calculated 
  values, 
  as 
  

   will 
  be 
  readily 
  seen 
  from 
  the 
  table, 
  is 
  only 
  to 
  be 
  obtained 
  near 
  

   the 
  boiling 
  point 
  of 
  the 
  zinc, 
  or 
  after 
  the 
  generation 
  of 
  the 
  

   vapor 
  has 
  begun 
  to 
  take 
  place 
  freely. 
  The 
  high 
  temperature 
  

   933-7° 
  on 
  the 
  first 
  day 
  was 
  obtained 
  by 
  overheating 
  the 
  appar- 
  

   atus 
  after 
  the 
  zinc 
  was 
  for 
  the 
  most 
  part 
  evaporated. 
  

  

  Electric 
  Oven. 
  — 
  The 
  second 
  bulb 
  of 
  this 
  sort 
  (No. 
  Ill) 
  was 
  

   heated 
  electrically. 
  

  

  The 
  coil 
  (see 
  fig. 
  1) 
  consisted 
  of 
  bare 
  nickel 
  wire 
  2'"'" 
  in 
  

   diameter 
  wound 
  upon 
  a 
  porcelain 
  or 
  fire-clay 
  tube 
  lying 
  hori- 
  

   zontally. 
  The 
  diameter 
  of 
  the 
  tube 
  was 
  i-S*^'" 
  (inside), 
  the 
  

   length' 
  35^"^ 
  and 
  the 
  thickness 
  0-3"'^' 
  to 
  0-5^^ 
  The 
  spaces 
  

   between 
  the 
  separate 
  turns 
  of 
  wire 
  (of 
  approximately 
  the 
  same 
  

   width 
  as 
  the 
  wire 
  itself) 
  were 
  filled 
  with 
  clay 
  which 
  baked 
  

   firmly 
  to 
  the 
  tube, 
  to 
  prevent 
  the 
  wire 
  from 
  slipping 
  and 
  short 
  

   circuiting 
  when 
  hot. 
  In 
  order 
  to 
  reduce 
  the 
  loss 
  of 
  heat 
  into 
  

  

  