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UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 1132 
Washington, D. C. 
PROFESSIONAL PAPER 
March 21, 1923 
THE RESULTS OF PHYSICAL TESTS 
OF ROAD-BUILDING ROCK 
FROM 1916 TO 1921, 
INCLUSIVE 
CONTENTS 
Page. 
Introduction 1 
Table I. — Results of physical tests of 
roadbuilding rock from 1916 to 1921, 
inclusive 2 
Crushing strength or compression test . 46 
Interpretation of results of physical tests . 46 
Page. 
Table II. — Results bf compression tests 
of rock made prior to January 1, 1916 . 48 
Table IH. — General limiting test values 
for broken stone 51 
Table IV.— Geographical distribution of 
rock samples tested from January 1, 
1916, to January 1, 1922 52 
WASHINGTON 
GOVERNMENT PRINTING OFFICE 
1923 
