﻿LIMESTONES 
  OF 
  NEW 
  YORK 
  AND 
  THEIR 
  ECONOMIC 
  VALUE 
  401 
  

  

  nesia 
  than 
  in 
  the 
  two 
  preceding 
  classes, 
  and 
  less 
  aluminum 
  and 
  

   iron 
  oxid 
  than 
  in 
  the 
  third 
  class. 
  Though 
  they 
  are 
  burned 
  so 
  

   thoroughly 
  that 
  there 
  is 
  but 
  a 
  small 
  per 
  cent 
  of 
  silicates 
  uncom- 
  

   bined, 
  still 
  as 
  Mr 
  Richardson 
  says, 
  all 
  of 
  these 
  cements 
  will 
  when 
  

   properly 
  burned 
  and 
  carefully 
  handled 
  give 
  successful 
  results 
  in 
  

   the 
  large 
  majority 
  of 
  cases. 
  As 
  a 
  rule 
  natural 
  cement 
  mortars 
  

   will 
  acquire 
  a 
  satisfactory 
  strength 
  with 
  sufficient 
  time, 
  though 
  it 
  

   may 
  have 
  originally 
  been 
  very 
  weak, 
  or 
  subjected 
  to 
  unfavorable 
  

   influences 
  due 
  to 
  the 
  conditions 
  under 
  which 
  it 
  was 
  used. 
  

  

  The 
  American 
  natural 
  cements 
  are 
  made 
  from 
  argillaceous 
  

   limestone 
  of 
  Silurian 
  or 
  Devonian 
  age. 
  In 
  New 
  York, 
  Pennsyl- 
  

   vania, 
  Maryland, 
  Virginia, 
  Georgia, 
  Kentucky, 
  Indiana 
  and 
  Wis- 
  

   consin 
  the 
  natural 
  rock 
  cements 
  all 
  come 
  from 
  the 
  same 
  horizon, 
  

   most 
  of 
  the 
  limestones 
  used 
  for 
  making 
  natural 
  cements 
  being 
  

   highly 
  magnesian. 
  The 
  following 
  analyses 
  illustrate 
  the 
  com- 
  

   position 
  of 
  these 
  natural 
  cement 
  rocks 
  from 
  different 
  points 
  in 
  

   the 
  U. 
  S. 
  In 
  sampling 
  a 
  cement 
  bed 
  for 
  analysis 
  and 
  test 
  the 
  

   greatest 
  care 
  has 
  to 
  be 
  used. 
  

  

  Lewis 
  considers 
  that 
  the 
  purest 
  and 
  the 
  most 
  homogeneous 
  

   deposit, 
  and 
  the 
  one 
  presenting 
  the 
  largest 
  acceptable 
  working 
  

   bed 
  is 
  that 
  of 
  the 
  Lehigh 
  valley. 
  This 
  is 
  now 
  being 
  used 
  to 
  

   make 
  portland 
  cements. 
  The 
  following 
  analyses 
  give 
  a 
  com- 
  

   position 
  of 
  natural 
  rock 
  cements. 
  

  

  Lewis 
  gives 
  following 
  analyses 
  of 
  rock 
  cements: 
  

  

  Locality 
  Si0 
  2 
  A1 
  2 
  3 
  Fe 
  2 
  3 
  CaO 
  MgO 
  Authority 
  

  

  Lawrenceville 
  29.00 
  10.40 
  32.35 
  19.92 
  A. 
  W. 
  Dow, 
  Wash. 
  D. 
  C. 
  

  

  Norton's 
  Rosendale 
  24.30 
  7.22 
  5.06 
  33.70 
  20.94 
  Booth, 
  Garr't, 
  Blair 
  

  

  Old 
  Newark 
  Rosendale 
  24.42 
  8.16 
  3.96 
  36.30 
  16.93 
  " 
  

  

  Lawrence 
  22.77 
  10.43 
  34.54 
  21.85 
  S.B.Newberry 
  

  

  Utica, 
  N. 
  Y 
  35.43 
  9.92 
  33.67 
  20.98 
  Gillmore 
  

  

  Cumberland 
  28.30 
  10.12 
  4.42 
  49.60 
  3.76 
  A.W.Dow 
  

  

  Milwaukee 
  25.16 
  6.33 
  1.71 
  36.08 
  18.38 
  Mfrs. 
  anal. 
  

  

  Lehigh 
  V. 
  Pa 
  26.50 
  9.40 
  2.00 
  53.50 
  2.40 
  Pa. 
  G. 
  S. 
  

  

  Louisville, 
  Ky 
  21.10 
  7.51 
  30.16 
  7.00 
  

  

  Cumberland 
  36.60 
  14.58 
  5.12 
  37.50 
  2.73 
  A.W.Dow 
  

  

  " 
  25.70 
  12.28 
  4.22 
  52.69 
  1.44 
  

  

  Round 
  top 
  30.02 
  13.55 
  3.00 
  44.58 
  2.76 
  

  

  " 
  28.36 
  9.85 
  3.07 
  45.04 
  2.82 
  " 
  

  

  Potomac 
  26.65 
  12.38 
  2.14 
  33.20 
  12.56 
  

  

  Vassy 
  (Fr.) 
  22.60 
  8.90 
  5.30 
  52.69 
  1.15 
  E. 
  Candlot 
  

  

  Yonne 
  23.40 
  12.90 
  3.30 
  47.70 
  1.05 
  " 
  

  

  Argenteuil 
  (Fr.) 
  29.55 
  8.35 
  4.10 
  47.50 
  3.85 
  " 
  

  

  Tsckerkasoff 
  (Russ.) 
  24.29 
  6.53 
  5.80 
  42.10 
  10.15 
  " 
  

  

  Sheppey 
  (Eng.) 
  45.60 
  50.30 
  2.85 
  Redgrave 
  

  

  Harwich 
  (Eng.) 
  47.00 
  , 
  48.00 
  4.00 
  " 
  

  

  