﻿LIMESTONES 
  OF 
  NEW 
  YORK 
  AND 
  THEIR 
  ECONOMIC 
  VALUE 
  441 
  

  

  The 
  composition 
  of 
  Mr 
  Water's 
  limestone 
  is: 
  

  

  Silica 
  -. 
  . 
  .. 
  3.96 
  

  

  Alumina 
  , 
  j 
  

  

  Ferric 
  oxid 
  f 
  1,7 
  ° 
  

  

  Lime 
  carbonate 
  91.27 
  

  

  Magnesium 
  carbonate 
  3 
  .78 
  

  

  100.71 
  

   Monroe 
  county 
  

  

  The 
  Niagara 
  limestone 
  extends 
  across 
  the 
  county 
  as 
  a 
  belt 
  

   several 
  miles 
  wide, 
  its 
  northern 
  edge 
  passing 
  through 
  the 
  towns 
  

   of 
  Penfield, 
  Brighton, 
  Ogden, 
  Gates 
  and 
  Sweden. 
  The 
  upper 
  

   magnesian 
  member 
  generally 
  forms 
  the 
  outcrops 
  and 
  the 
  

   weathered 
  surface 
  of 
  the 
  rock 
  has 
  a 
  peculiar 
  granular 
  and 
  spongy 
  

   appearance. 
  

  

  The 
  upper 
  member, 
  or 
  Guelph 
  limestone, 
  is 
  a 
  grayish 
  brown, 
  

   finely 
  crystalline 
  limestone 
  containing 
  numerous 
  small 
  cavities. 
  

   The 
  rock 
  is 
  very 
  low 
  in 
  silica 
  and 
  has 
  a 
  large 
  amount 
  of 
  magnesia, 
  

   making 
  it 
  well 
  adapted 
  for 
  refractory 
  linings 
  in 
  furnaces. 
  

  

  The 
  lower 
  beds 
  of 
  Niagara 
  limestone 
  are 
  hard, 
  compact 
  and 
  

   generally 
  highly 
  siliceous 
  in 
  Monroe 
  county. 
  

  

  The 
  Niagara 
  shale 
  underlies 
  the 
  Niagara 
  limestone 
  and 
  the 
  

   transitional 
  beds 
  between 
  the 
  two 
  sometimes 
  furnish 
  a 
  natural 
  

   cement 
  rock. 
  Beds 
  of 
  this 
  nature 
  outcrop 
  at 
  Shelby 
  falls 
  in 
  the 
  

   town 
  of 
  Barre. 
  

  

  The 
  Guelph 
  limestone 
  is 
  well 
  exposed 
  in 
  the 
  quarry 
  of 
  the 
  

   Rochester 
  lime 
  co. 
  at 
  Brighton 
  two 
  miles 
  east 
  of 
  Rochester. 
  The 
  

   rock 
  is 
  used 
  for 
  lime 
  and 
  gives 
  a 
  lumpy 
  product 
  of 
  yellowish 
  

   color. 
  The 
  following 
  analysis 
  sets 
  forth 
  well 
  its 
  magnesian 
  char- 
  

   acter 
  and 
  its 
  comparative 
  freedom 
  from 
  silica: 
  

  

  Silica 
  1.12 
  

  

  Alumina 
  ' 
  27 
  

  

  Ferric 
  oxid 
  .39 
  

  

  Lime 
  29.38 
  

  

  Magnesia 
  22 
  . 
  10 
  

  

  Carbon 
  dioxid 
  47.39 
  

  

  100.65 
  

  

  