﻿CLAYS 
  OF 
  NEW 
  YOEK 
  801 
  

  

  iron 
  scoops 
  on 
  their 
  periphery. 
  As 
  the 
  wheels 
  revolve 
  the 
  scoops 
  

   catch 
  up 
  a 
  portion 
  of 
  the 
  sand 
  which 
  has 
  settled 
  in 
  the 
  trough, 
  and, 
  

   as 
  each 
  scoop 
  reaches 
  the 
  upper 
  limit 
  of 
  its 
  turn 
  on 
  the 
  wheel, 
  it, 
  

   by 
  its 
  inverted 
  position, 
  drops 
  the 
  sand 
  outside 
  the 
  trough. 
  These 
  

   sand 
  wheels 
  are 
  a 
  help, 
  but 
  it 
  is 
  often 
  necessary 
  in 
  addition 
  to 
  keep 
  

   a 
  man 
  shoveling 
  the 
  sand 
  from 
  the 
  trough. 
  

  

  If 
  the 
  sand 
  is 
  finer 
  it 
  is 
  not 
  dropped 
  so 
  quickly, 
  and, 
  distributed 
  

   more 
  evenly 
  along 
  the 
  trough, 
  does 
  not 
  clog 
  it 
  up 
  so 
  fast. 
  

  

  The 
  zigzag 
  arrangement 
  of 
  the 
  troughing 
  has 
  been 
  objected 
  to 
  

   by 
  some, 
  as 
  it 
  produces 
  irregularities 
  in 
  the 
  current, 
  causing 
  the 
  

   sand 
  to 
  bank 
  up 
  in 
  the 
  corners, 
  at 
  the 
  bends 
  and 
  at 
  certain 
  points 
  

   along 
  the 
  sides 
  of 
  the 
  troughing. 
  (E. 
  Hotop. 
  Thonindustrie 
  zeit- 
  

   ung. 
  1893) 
  The 
  effect 
  is 
  to 
  narrow 
  the 
  channel, 
  and 
  consequently 
  

   increase 
  the 
  velocity 
  of 
  the 
  current, 
  thereby 
  causing 
  the 
  fine 
  sand 
  

   to 
  be 
  carried 
  still 
  farther 
  toward 
  the 
  settling 
  tank. 
  This 
  difficulty, 
  

   which 
  is 
  not 
  often 
  serious, 
  has 
  been 
  obviated 
  either 
  by 
  having 
  the 
  

   troughing 
  straight 
  or 
  by 
  allowing 
  the 
  water 
  and 
  suspended 
  clay 
  

   as 
  they 
  come 
  from 
  the 
  log 
  washer 
  to 
  pass 
  through 
  a 
  section 
  of 
  

   straight 
  trough, 
  and 
  from 
  this 
  into 
  another, 
  of 
  the 
  same 
  depth 
  but 
  

   5 
  or 
  6 
  times 
  the 
  width, 
  and 
  divided, 
  by 
  several 
  longitudinal 
  par- 
  

   titions. 
  The 
  water 
  and 
  the 
  clay 
  then 
  pass 
  into 
  a 
  third 
  section, 
  

   twice 
  as 
  wide 
  as 
  the 
  second, 
  and 
  divided 
  by 
  twice 
  the 
  number 
  of 
  

   longitudinal 
  divisions. 
  By 
  this 
  means 
  the 
  water 
  moves 
  only 
  in 
  a 
  

   straight 
  course, 
  but 
  as 
  it 
  is 
  being 
  continually 
  spread 
  out 
  over 
  a 
  

   wider 
  space 
  it 
  flows 
  with 
  an 
  ever 
  decreasing 
  velocity. 
  

  

  By 
  the 
  time 
  the 
  water 
  has 
  reached 
  the 
  end 
  of 
  the 
  troughing 
  

   nearly 
  all 
  the 
  coarse 
  grains 
  have 
  been 
  dropped 
  and 
  the 
  water 
  is 
  

   ready 
  to 
  be 
  led 
  into 
  the 
  settling 
  vats, 
  but 
  as 
  a 
  farther 
  and 
  necessary 
  

   precaution 
  it 
  is 
  discharged 
  on 
  a 
  screen 
  of 
  100 
  meshes 
  to 
  the 
  linear 
  

   inch, 
  with 
  the 
  object 
  of 
  removing 
  any 
  coarse 
  particles 
  that 
  might 
  

   remain, 
  and 
  also 
  eliminating 
  sticks 
  and 
  other 
  bits 
  of 
  floating 
  dirt. 
  

  

  Two 
  kinds 
  of 
  screens 
  can 
  be 
  used, 
  the 
  first 
  stationary, 
  the 
  second 
  

   revolving. 
  The 
  stationary 
  screen 
  is 
  simply 
  a 
  frame 
  covered 
  with 
  

   a 
  copper 
  cloth 
  and 
  set 
  at 
  a 
  slight 
  angle. 
  The 
  water 
  and 
  suspended 
  

  

  