﻿678 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  are 
  called, 
  before 
  tliej 
  are 
  allowed 
  to 
  escape 
  into 
  the 
  kiln. 
  The 
  

   fire 
  then 
  passes 
  downward 
  through 
  the 
  product 
  and 
  out 
  through 
  

   the 
  openings 
  in 
  the 
  floor 
  of 
  the 
  kiln 
  to 
  the 
  flues, 
  and 
  from 
  these 
  to 
  

   the 
  stack, 
  or 
  chimneys. 
  The 
  hight 
  of 
  the 
  bags 
  on 
  the 
  inside 
  wall 
  

   of 
  the 
  kiln 
  varies, 
  and 
  depends 
  partly 
  on 
  the 
  type 
  of 
  kiln, 
  and 
  

   largely 
  on 
  the 
  individual 
  opinion 
  of 
  the 
  manufacturer. 
  

  

  There 
  may 
  be 
  one 
  main 
  stack 
  or, 
  sometimes, 
  there 
  are 
  several 
  

   small 
  ones 
  on 
  each 
  kiln. 
  The 
  down-draft 
  kilns 
  are 
  either 
  rect- 
  

   angular 
  or 
  round 
  in 
  shape. 
  The 
  average 
  capacity 
  of 
  the 
  former 
  is 
  

   about 
  150,000 
  brick, 
  while 
  that 
  of 
  the 
  latter 
  varies 
  with 
  the 
  diam- 
  

   eter, 
  which 
  is 
  from 
  15 
  to 
  25 
  feet. 
  

  

  The 
  percentage 
  of 
  salmon 
  brick 
  is 
  much 
  smaller 
  in 
  a 
  down- 
  

   draft 
  than 
  in 
  an 
  up-draft 
  kiln, 
  and 
  seldom 
  exceeds 
  16^. 
  Those 
  

   bricks 
  which 
  are 
  on 
  the 
  top 
  of 
  the 
  kiln 
  receive 
  the 
  greatest 
  

   amount 
  of 
  heat, 
  but 
  as 
  there 
  is 
  no 
  pressure 
  on 
  them 
  they 
  do 
  not 
  

   become 
  misshapen, 
  and 
  consequently 
  on 
  account 
  of 
  their 
  great 
  

   hardness 
  and 
  density 
  are 
  often 
  sold 
  under 
  the 
  name 
  of 
  " 
  rough 
  

   hard 
  '^ 
  and 
  serve 
  excellently 
  for 
  use 
  in 
  damp 
  situations 
  and 
  for 
  

   sewer 
  work. 
  

  

  Several 
  types 
  of 
  down-draft 
  kiln 
  are 
  illustrated 
  in 
  the 
  report. 
  

  

  Down-draft 
  kilns 
  sometimes 
  have 
  two 
  sets 
  of 
  fireplaces, 
  the 
  

   one 
  connecting 
  with 
  the 
  bags 
  on 
  the 
  inside 
  of 
  the 
  kiln 
  and 
  the 
  other 
  

   leading 
  directly 
  into 
  the 
  interior. 
  The 
  kiln 
  may 
  thus 
  be 
  worked 
  

   either 
  as 
  an 
  up 
  or 
  a 
  down-draft, 
  the 
  former 
  being 
  used 
  during 
  

   the 
  water-smoking 
  and 
  the 
  latter 
  during 
  the 
  burning. 
  ' 
  

  

  Continuous 
  kilns. 
  These 
  consist 
  of 
  a 
  series 
  of 
  chambers! 
  separated 
  

   by 
  either 
  temporary 
  or 
  permanent 
  walls. 
  The 
  fire 
  is 
  started 
  in 
  the 
  

   first, 
  and 
  as 
  the 
  burning 
  proceeds 
  the 
  heat 
  from 
  the 
  burning 
  cham- 
  

   ber 
  is 
  conducted 
  through 
  the 
  succeeding 
  ones 
  either 
  through 
  flues 
  in 
  

   the 
  wall 
  or 
  pipes 
  connecting 
  the 
  openings 
  in 
  the 
  roof 
  of 
  the 
  kiln. 
  In 
  

   this 
  way, 
  by 
  means 
  of 
  the 
  exhaust 
  heat, 
  the 
  temperature 
  of 
  the 
  suc- 
  

   ceeding 
  chambers 
  is 
  raised, 
  so 
  that 
  less 
  fuel 
  is 
  required. 
  The 
  heat 
  

   from 
  a 
  buminer 
  chamber 
  can 
  not 
  as 
  a 
  rule 
  be 
  earned 
  safely 
  tlirough 
  

  

  