﻿CLAYS 
  OF 
  IsEW 
  YORK 
  737 
  

  

  Below 
  is 
  given 
  an 
  analysis 
  of 
  the 
  clay. 
  

  

  Silica 
  59.05 
  

  

  Alumina 
  22 
  . 
  11 
  

  

  Peroxid 
  of 
  iron 
  6 
  . 
  54 
  

  

  Lime 
  2.19 
  

  

  Magnesia 
  2 
  . 
  64 
  

  

  Alkalis 
  6.22 
  

  

  98.75 
  

  

  The 
  plasticity 
  of 
  the 
  clay 
  is 
  quite 
  well 
  shown 
  by 
  the 
  amount 
  of 
  

   water 
  required 
  to 
  work 
  it 
  up, 
  viz. 
  4:0 
  fc. 
  The 
  air 
  shrinkage 
  was 
  8^; 
  

   when 
  burned 
  at 
  .08, 
  which 
  is 
  about 
  the 
  temperature 
  attained 
  in 
  the 
  

   scove-kilns, 
  the 
  shrinkage 
  was 
  9^. 
  At 
  this 
  point, 
  however, 
  incipient 
  

   fusion 
  had 
  barely 
  begun. 
  When 
  heated 
  above 
  this 
  point 
  the 
  shrink- 
  

   age 
  increased 
  quite 
  rapidly, 
  so 
  that 
  at 
  vitrification, 
  which 
  occurred 
  

   at 
  cone 
  1, 
  the 
  total 
  shrinkage 
  was 
  16^. 
  At 
  incipient 
  fusion 
  the 
  

   clay 
  burns 
  red; 
  at 
  vitrification 
  a 
  very 
  deep 
  red. 
  Viscosity 
  occurs 
  at 
  

   cone 
  4. 
  The 
  high 
  shrinkage 
  of 
  this 
  clay 
  would 
  probably 
  interfere 
  

   with 
  its 
  use 
  alone 
  for 
  vitrified 
  wares. 
  The 
  tensile 
  strength 
  of 
  the 
  

   air-dried 
  briquettes 
  ranged 
  from 
  133 
  to 
  140 
  pounds 
  a 
  square 
  inch, 
  

   but 
  one 
  gave 
  a 
  minimum 
  of 
  108 
  pounds. 
  The 
  clay 
  contains 
  .7^ 
  of 
  

   soluble 
  salts. 
  

  

  FJsliers 
  Island, 
  Suifolk 
  co. 
  The 
  extensive 
  deposit 
  of 
  clay 
  at 
  this 
  

   locality 
  is 
  worked 
  by 
  the 
  Fishers 
  Island 
  brick 
  manufacturing 
  co., 
  

   whose 
  plant 
  has 
  a 
  capacity 
  of 
  about 
  15,000,000. 
  The 
  yards 
  are 
  

   situated 
  on 
  the 
  north 
  shore 
  of 
  the 
  island 
  between 
  Clay 
  point 
  and 
  

   Hawks 
  neck 
  point. 
  About 
  1500 
  feet 
  from 
  the 
  shore 
  is 
  the 
  bank 
  

   of 
  clay 
  of 
  a 
  reddish 
  color 
  and 
  thinly 
  stratified, 
  the 
  layers 
  of 
  clay 
  

   being 
  separated 
  by 
  very 
  thin 
  ones 
  of 
  sand. 
  In 
  most 
  places, 
  how- 
  

   ever, 
  the 
  mass 
  has 
  been 
  disturbed 
  by 
  glacial 
  movements. 
  There 
  

   is 
  a 
  stripping 
  of 
  20 
  or 
  30 
  feet 
  of 
  a 
  whitish 
  sand, 
  the 
  finer 
  portions 
  

   of 
  which 
  can 
  be 
  used 
  for 
  tempering. 
  Their 
  present 
  working 
  face 
  

   is 
  30 
  feet 
  above 
  tide 
  at 
  its 
  base, 
  and 
  the 
  clay, 
  it 
  is 
  declared, 
  has 
  a 
  

  

  