﻿CLAYS 
  OF 
  NEW 
  YORK 
  803 
  

  

  most 
  of 
  the 
  clear 
  water 
  is 
  drawn 
  off; 
  the 
  cream-like 
  mass 
  of 
  kaolin, 
  

   and 
  water 
  in 
  the 
  bottom 
  of 
  the 
  vat 
  is 
  drawn 
  off 
  by 
  means 
  of 
  slip 
  

   pumps 
  and 
  forced 
  by 
  these 
  into 
  the 
  presses. 
  

  

  The 
  presses 
  consist 
  simply 
  of 
  flat, 
  iron 
  or 
  wooden 
  frames 
  be- 
  

   tween 
  which 
  are 
  flat 
  canvas 
  bags. 
  These 
  bags 
  are 
  connected 
  by 
  

   nipples 
  with 
  a 
  supply 
  tube 
  from 
  the 
  slip 
  pumps, 
  and 
  by 
  means 
  of 
  

   the 
  pressure 
  from 
  the 
  pumps 
  nearly 
  all 
  of 
  the 
  water 
  is 
  forced 
  out 
  of 
  

   the 
  kaolin 
  and 
  through 
  the 
  canvas. 
  When 
  as 
  much 
  water 
  as 
  pos- 
  

   sible 
  is 
  squeezed 
  out, 
  the 
  press 
  is 
  opened 
  and 
  the 
  sheets 
  of 
  semi- 
  

   dry 
  kaolin 
  are 
  taken 
  out. 
  It 
  is 
  then 
  dried 
  either 
  on 
  racks 
  in 
  the 
  

   open 
  air 
  or 
  in 
  a 
  steam-heated 
  room. 
  

  

  As 
  for 
  every 
  ton 
  of 
  crude 
  kaolin 
  usually 
  only 
  about 
  |- 
  or 
  -^ 
  of 
  

   a 
  ton 
  of 
  washed 
  kaolin 
  is 
  obtained, 
  it 
  is 
  desirable 
  to 
  have 
  the 
  wash- 
  

   ing 
  plant 
  at 
  the 
  mines, 
  to 
  avoid 
  the 
  hauling 
  of 
  60^ 
  to 
  YO^ 
  of 
  useless 
  

   sand 
  which 
  has 
  to 
  be 
  washed 
  out 
  before 
  the 
  kaolin 
  can 
  be 
  used 
  or 
  

   even 
  placed 
  on 
  the 
  market. 
  

  

  Tempering 
  

  

  Chaser 
  mill. 
  This 
  consists 
  of 
  a 
  circular 
  iron 
  pan 
  in 
  which 
  

   revolves 
  a 
  frame 
  bearing 
  two 
  heavy 
  iron 
  wheels, 
  about 
  30 
  to 
  36 
  

   inches 
  in 
  diameter. 
  As 
  this 
  frame 
  revolves, 
  the 
  wheels, 
  by 
  means 
  of 
  

   a 
  gearing, 
  travel 
  from 
  the 
  center 
  to 
  the 
  circumference 
  of 
  the 
  pan 
  

   and 
  then 
  back. 
  The 
  clay 
  is 
  dumped 
  into 
  the 
  pan, 
  water 
  added, 
  

   and 
  by 
  the 
  action 
  of 
  the 
  wheels, 
  grinding 
  and 
  cutting 
  it 
  up, 
  it 
  is 
  

   ground 
  and 
  mixed 
  in 
  from 
  one 
  to 
  two 
  hours. 
  The 
  action 
  of 
  such 
  a 
  

   machine 
  is 
  quite 
  thorough, 
  but 
  requires 
  considerable 
  power 
  to 
  

   operate 
  it. 
  It 
  is 
  sometimes 
  used 
  for 
  stoneware 
  clays. 
  

  

  Wet 
  pans. 
  The 
  action 
  of 
  these 
  has 
  already 
  been 
  described, 
  

   under 
  bricks. 
  This 
  machine 
  is 
  occasionally 
  used 
  in 
  the 
  preparation 
  

   of 
  pottery 
  clays, 
  and 
  is 
  fully 
  as 
  eflicient 
  in 
  its 
  action 
  as 
  the 
  pre- 
  

   ceding 
  one, 
  while 
  it 
  has 
  the 
  advantage 
  of 
  operating 
  continuously 
  

   and 
  also 
  of 
  requiring 
  less 
  power. 
  The 
  clay 
  is 
  also 
  ground 
  and 
  mixed 
  

   much 
  more 
  quickly 
  in 
  a 
  wet 
  pan 
  than 
  in 
  a 
  chasing 
  mill; 
  and 
  the 
  

   greater 
  width 
  of 
  the 
  wheels, 
  and 
  the 
  presence 
  of 
  scrapers 
  to 
  throw 
  

   the 
  clay 
  under 
  them, 
  insures 
  the 
  thorough 
  grinding 
  of 
  any 
  lumps 
  

  

  