﻿464 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  There 
  are 
  certain 
  layers 
  on 
  the 
  west 
  side 
  of 
  the 
  quarry 
  which 
  

   should 
  be 
  avoided 
  as 
  they 
  run 
  more 
  siliceous. 
  In 
  structure 
  these 
  

   layers 
  are 
  thinner 
  than 
  those 
  of 
  the 
  purer 
  stone 
  and 
  more 
  finely 
  

   crystalline. 
  Their 
  composition 
  was 
  found 
  to 
  be 
  as 
  follows: 
  

  

  Silica 
  6.75 
  

  

  Ferric 
  oxid 
  1 
  . 
  08 
  

  

  Alumina 
  3.02 
  

  

  Lime 
  28.32 
  

  

  Magnesia 
  17 
  . 
  94 
  

  

  The 
  best 
  quality 
  of 
  stone 
  makes 
  a 
  very 
  white 
  lump 
  lime. 
  

  

  The 
  quarries 
  at 
  Tuckahoe, 
  Westchester 
  co. 
  are 
  most 
  exten- 
  

   sive 
  and 
  are 
  all 
  located 
  in 
  the 
  same 
  stratum, 
  which 
  extends 
  north- 
  

   east 
  and 
  southwest 
  and 
  has 
  a 
  thickness 
  of 
  about 
  40 
  feet. 
  

  

  The 
  firms 
  operating 
  the 
  quarries 
  are 
  O'Connell 
  & 
  Hillery, 
  Nor- 
  

   cross 
  Bros, 
  and 
  the 
  Tuckahoe 
  marble 
  co. 
  also 
  known 
  as 
  J. 
  Sin- 
  

   clair 
  & 
  Co. 
  

  

  The 
  rock 
  in 
  all 
  of 
  these 
  quarries 
  is 
  a 
  magnesian 
  limestone 
  of 
  

   granular 
  character 
  and 
  moderately 
  hard. 
  Its 
  character 
  is 
  quite 
  

   constant. 
  The 
  beds 
  dip 
  steeply 
  to 
  the 
  west, 
  and 
  those 
  forming 
  

   the 
  walls 
  of 
  the 
  quarry 
  are 
  very 
  micaceous. 
  

  

  O'Connell 
  & 
  Hillery 
  's 
  is 
  the 
  most 
  southern 
  quarry 
  and 
  is 
  but 
  

   a 
  short 
  distance 
  from 
  the 
  Tuckahoe 
  railroad 
  station. 
  The 
  rock 
  

   is 
  used 
  chiefly 
  for 
  making 
  lime,, 
  but 
  in 
  recent 
  years 
  the 
  manu- 
  

   facture 
  of 
  marble 
  dust 
  has 
  also 
  been 
  begun. 
  

  

  The 
  following 
  analysis 
  of 
  the 
  stone 
  was 
  furnished 
  by 
  the 
  com- 
  

   pany: 
  

  

  Carbonate 
  of 
  lime 
  70.10 
  

  

  Carbonate 
  of 
  magnesia 
  25 
  . 
  40 
  

  

  Insoluble 
  matter 
  2 
  .40 
  

  

  97.90 
  

  

  The 
  Tuckahoe 
  marble 
  co.'s 
  quarry 
  is 
  three 
  quarters 
  of 
  a 
  

   mile 
  to 
  the 
  north. 
  The 
  quarry 
  is 
  about 
  400 
  feet 
  long 
  and 
  40 
  feet 
  

   deep, 
  and 
  up 
  to 
  the 
  present 
  time 
  the 
  stone 
  has 
  been 
  used 
  for 
  

   building 
  purposes 
  only. 
  

  

  