﻿of 
  various 
  Substances 
  on 
  Solidification. 
  213 
  

  

  the 
  walls 
  of 
  the 
  vessel 
  being 
  about 
  j 
  in. 
  in 
  thickness." 
  1 
  It 
  was 
  per- 
  

   fectly 
  smooth 
  in 
  the 
  inside, 
  and 
  the 
  plane 
  of 
  the 
  lip 
  of 
  the 
  open 
  

   neck 
  was 
  carefully 
  made 
  parallel 
  to 
  the 
  plane 
  of 
  the 
  base. 
  This 
  

   vessel 
  weighed, 
  when 
  empty, 
  184-75 
  lbs. 
  avoirdupois. 
  The 
  orifice 
  of 
  

   the 
  neck 
  being 
  levelled 
  as 
  the 
  vessel 
  stood 
  upon 
  the 
  platform 
  of 
  the 
  

   weighing-apparatus, 
  it 
  was 
  filled 
  up 
  to 
  the 
  exact 
  level 
  of 
  the 
  neck 
  with 
  

   water 
  at 
  a 
  temperature 
  of 
  60°*5 
  Fahr., 
  and 
  again 
  weighed. 
  Deducting 
  the 
  

   weight 
  of 
  the 
  empty 
  vessel, 
  the 
  weight 
  of 
  its 
  contents 
  of 
  water 
  was 
  found 
  

   to 
  be 
  94-15 
  lbs. 
  avoirdupois. 
  From 
  the 
  known 
  volume 
  and 
  weight 
  of 
  the 
  

   imperial 
  gallon 
  of 
  distilled 
  water, 
  the 
  capacity 
  of 
  the 
  vessel 
  was 
  therefore 
  

   at 
  60° 
  Fahr. 
  =2605-5 
  cubic 
  inches. 
  As 
  a 
  check 
  upon 
  the 
  results, 
  both 
  

   as 
  to 
  weight 
  and 
  capacity, 
  the 
  water 
  was 
  measured 
  into 
  the 
  vessel 
  

   from 
  accurate 
  glass 
  standards 
  of 
  volume. 
  The 
  water 
  employed 
  was 
  that 
  

   from 
  the 
  well 
  at 
  Messrs. 
  Maudslay, 
  Sons, 
  and 
  Field 
  s 
  Engine 
  Works, 
  

   Lambeth, 
  where 
  these 
  experiments 
  were 
  conducted, 
  and 
  to 
  whose 
  liberality 
  

   the 
  author 
  owes 
  the 
  means 
  of 
  having 
  performed 
  them. 
  The 
  specific 
  

   gravity 
  of 
  this 
  well-water 
  did 
  not 
  very 
  materially 
  exceed 
  that 
  of 
  distilled 
  

   water, 
  being 
  about 
  1*0004 
  • 
  but 
  if 
  we 
  apply 
  the 
  necessary 
  correction, 
  the 
  

   weight 
  of 
  the 
  contents 
  of 
  the 
  iron 
  vessel 
  of 
  distilled 
  water 
  at 
  60° 
  Fahr. 
  

   is 
  94-112 
  lbs. 
  avoirdupois. 
  The 
  vessel 
  being 
  emptied, 
  carefully 
  dried 
  and 
  

   warmed, 
  and 
  stood 
  upon 
  a 
  hard 
  rammed 
  bed 
  of 
  dry 
  sand 
  with 
  its 
  neck 
  

   perfectly 
  level 
  as 
  before, 
  was 
  now 
  filled 
  perfectly 
  level 
  to 
  the 
  brim 
  with 
  

   molten 
  cast 
  iron. 
  As 
  the 
  temperature 
  of 
  the 
  vessel 
  itself 
  rapidly 
  rose 
  by 
  

   contact 
  with 
  the 
  large 
  mass 
  of 
  molten 
  iron 
  within 
  it, 
  and 
  by 
  its 
  dilata- 
  

   tion 
  had 
  its 
  capacity 
  enlarged, 
  so 
  the 
  top 
  surface 
  of 
  the 
  liquid 
  cast 
  

   iron 
  within 
  it 
  rapidly 
  sank, 
  fresh 
  additions 
  of 
  molten 
  iron 
  being 
  constantly 
  

   made 
  to 
  maintain 
  its 
  top 
  surface 
  level 
  with 
  the 
  brim. 
  This 
  was 
  continued 
  

   until 
  the 
  whole 
  of 
  the 
  exterior 
  of 
  the 
  vessel 
  was 
  seen 
  to 
  have 
  arrived 
  at 
  a 
  

   clear 
  yellow 
  heat, 
  beyond 
  which 
  no 
  increase 
  to 
  its 
  temperature 
  took 
  place. 
  

   At 
  about 
  twenty 
  minutes 
  after 
  the 
  molten 
  iron 
  was 
  first 
  poured 
  into 
  the 
  

   vessel, 
  this 
  point 
  was 
  reached, 
  the 
  feeding 
  in 
  of 
  additional 
  iron 
  being 
  dis- 
  

   continued 
  a 
  few 
  minutes 
  previously. 
  The 
  whole 
  being 
  left 
  to 
  cool 
  for 
  

   three 
  days, 
  the 
  vessel 
  full 
  of 
  the 
  now 
  cold 
  and 
  solid 
  cast 
  iron 
  was 
  again 
  

   weighed; 
  on 
  deducting, 
  as 
  before, 
  the 
  weight 
  of 
  the 
  empty 
  vessel, 
  the 
  weight 
  

   of 
  the 
  cast 
  iron 
  which 
  filled 
  it 
  was 
  found 
  to 
  be 
  645*75 
  lbs., 
  which, 
  with 
  

   certain 
  corrections 
  to 
  be 
  yet 
  noticed, 
  was 
  the 
  weight 
  of 
  cast 
  iron 
  which, 
  

   when 
  in 
  the 
  molten 
  state, 
  was 
  equal 
  to 
  the 
  capacity 
  of 
  the 
  conical 
  iron 
  

   vessel 
  in 
  its 
  expanded 
  state 
  due 
  to 
  its 
  exalted 
  temperature. 
  "We 
  have 
  

   now 
  to 
  determine 
  what 
  was 
  the 
  capacity 
  of 
  the 
  vessel 
  in 
  this 
  expanded 
  

   state. 
  The 
  temperature 
  at 
  which 
  cast 
  iron 
  melts 
  may 
  be 
  admitted 
  as 
  

   about 
  2400° 
  Fahr. 
  ; 
  but 
  as 
  iron 
  tapped 
  from 
  the 
  cupola 
  is 
  always 
  above 
  

   its 
  melting-point, 
  we 
  may 
  admit 
  that 
  it 
  was 
  poured 
  into 
  the 
  vessel 
  at 
  

   2600° 
  or 
  2700° 
  Fahr., 
  the 
  surplus 
  heat 
  in 
  the 
  cast 
  iron, 
  whose 
  mass 
  was 
  

   about 
  four 
  times 
  that 
  of 
  the 
  wrought-iron 
  vessel 
  which 
  contained 
  it, 
  being 
  

   given 
  off 
  in 
  the 
  first 
  instance 
  to 
  heat 
  the 
  latter. 
  The 
  temperature 
  at 
  which 
  

  

  