﻿TESTS 
  OF 
  ROAD 
  MATERIAL 
  IO9 
  

  

  contains 
  the 
  specific 
  density 
  of 
  the 
  stones 
  ; 
  column 
  2, 
  the 
  coefficients 
  ot 
  

   abrasion 
  (determined 
  in 
  the 
  manner 
  previously 
  described) 
  ; 
  the 
  next 
  

   column 
  gives 
  the 
  number 
  of 
  blows 
  required 
  to 
  stress 
  the 
  i 
  in. 
  briquettes 
  

   to 
  their 
  elastic 
  limits 
  ; 
  column 
  4 
  gives 
  the 
  same 
  data 
  for 
  the 
  first 
  testing 
  

   of 
  the 
  30 
  gram 
  (463) 
  briquettes 
  prepared 
  for 
  the 
  recementation 
  test, 
  

   and 
  the 
  next 
  column 
  gives 
  the 
  number 
  of 
  blows 
  that 
  the 
  recemented 
  

   briquettes 
  will 
  stand 
  before 
  reaching 
  their 
  elastic 
  limits." 
  

  

  Through 
  the 
  courtesy 
  of 
  the 
  commission 
  six 
  specimens 
  of 
  typical 
  New 
  

   York 
  rocks 
  were 
  subjected 
  to 
  the 
  abrasion 
  test 
  with 
  results 
  which 
  are 
  

   noted 
  in 
  the 
  following 
  table 
  ; 
  which 
  also 
  gives 
  the 
  results 
  of 
  some 
  tests 
  ot 
  

   Massachusetts 
  rocks. 
  

  

  