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UNITED STATES DEPARTMENT OF AGRICULTURE 

 BULLETIN No. 949 



Contribution from the Bureau of Public Roads 

 THOMAS H. MacDONALD, Chief 



Washington, D. C. * ▼ October 10, 1921 



STANDARD AND TENTATIVE METHODS 



OF SAMPLING AND TESTING 



HIGHWAY MATERIALS 



Recommended by the / 



SECOND CONFERENCE OF ST^TE HIGHWAY TESTING ENGINEERS 



AND CHEMISTS 



Washington, D. C, February 23 to 27, 1920 



CONTENTS 



Page I Page 



Introduction 1 Recommended Standard Methods of 



Tests for Nonbituminous Road Ma- Sampling 69 



terials 3 | Miscellaneous Matter 75 



Tests for Bituminous Road Materials . . 36 Forms for Recording and Reporting Re- 

 Tentative Tests . 62 I suits 79 



WASHINGTON 

 GOVERNMENT PRINTING OFFICE 



1921 



