﻿CLAYS 
  Of 
  new 
  yOrk 
  785 
  

  

  Fire 
  brick 
  when, 
  molded 
  are 
  commonly 
  set 
  on 
  the 
  floor 
  to 
  dry 
  

   for 
  a 
  few 
  hours, 
  after 
  which 
  they 
  are 
  repressed. 
  

  

  They 
  are 
  then 
  loaded 
  on 
  cars 
  and 
  sent 
  to 
  the 
  drying 
  tunnels. 
  

   (See 
  description 
  under 
  Drying 
  of 
  bricks, 
  p. 
  668) 
  The 
  rapidity 
  with 
  

   which 
  the 
  drying 
  can 
  be 
  carried 
  on 
  depends 
  on 
  the 
  porosity 
  of 
  the 
  

   clay, 
  its 
  plasticity 
  and 
  the 
  size 
  of 
  the 
  molded 
  object. 
  

  

  The 
  burning 
  of 
  fire 
  brick 
  is 
  done 
  either 
  in 
  up 
  or 
  down-di'aft 
  

   kilns, 
  of 
  either 
  circular 
  or 
  rectangular 
  form. 
  

  

  Behavior 
  of 
  refractory 
  brick 
  when 
  heated 
  

   In 
  some 
  experiments 
  recently 
  made 
  by 
  J. 
  D. 
  Pennock^ 
  to 
  deter- 
  

   mine 
  the 
  heat 
  conductivity, 
  expansion, 
  and 
  fusibility 
  of 
  refractory 
  

   brick, 
  bricks 
  made 
  of 
  Grecian 
  magnesite, 
  American 
  magnesite^ 
  

   silica 
  brick, 
  and 
  coke 
  oven 
  tiling 
  made 
  in 
  Belgium, 
  were 
  used. 
  

  

  In 
  the 
  charts 
  and 
  detailed 
  figures 
  given 
  by 
  Mr 
  Pennock 
  it 
  is 
  

   shown 
  that 
  the 
  Grecian 
  magnesite 
  conducts 
  heat 
  the 
  most 
  readily, 
  

   the 
  American 
  next, 
  then 
  the 
  silica 
  brick, 
  while 
  the 
  coke 
  oven 
  brick 
  

   is 
  the 
  poorest 
  conductor. 
  The 
  poor 
  conductivity 
  of 
  the 
  coke 
  oven 
  

   brick 
  is 
  thought 
  to 
  lie 
  in 
  its 
  purity 
  and 
  density. 
  

  

  Expansion 
  tests 
  of 
  fire 
  brick 
  

  

  Ini 
  h 
  Inch 
  

  

  Grecian 
  magnesite 
  . 
  07 
  0.11 
  

  

  " 
  07 
  .11 
  

  

  American 
  magnesite 
  .067 
  .10 
  

  

  " 
  057 
  .088 
  

  

  Coke 
  oven 
  tiling 
  .05 
  .076 
  

  

  " 
  05 
  .076 
  

  

  The 
  expansion 
  test 
  was 
  made 
  by 
  supporting 
  a 
  core 
  of 
  the 
  brick 
  in 
  

   a 
  horizontal 
  position. 
  One 
  end 
  was 
  against 
  a 
  support 
  and 
  the 
  

   other 
  against 
  a 
  movable 
  lever. 
  The 
  core 
  was 
  heated 
  by 
  means 
  of 
  

   burners 
  placed 
  underneath. 
  

  

  1 
  Trans. 
  Amer. 
  inst. 
  min. 
  eng., 
  September, 
  1896. 
  p. 
  263. 
  

  

  