2 BULTJETIN 1036, U. S. DEPARTMENT OF AGPJCULTURE. 



the variations of creosote with different processes of manufacture. 

 The bulletin also presents descriptions of the different methods of 

 testing creosotes which have been used or suggested, and particularly 

 those now adopted as standard by the various associations interested 

 in wood preservation, and gives a discussion of the value of the 

 methods of testing. 



The bulletin has been divided into four parts. , Part I includes the 

 introduction, a description of tars, and an account of the manu- 

 facture of creosote. Part II is a presentation for the first time of the 

 results of researches by the author and his coworkers in the Forest 

 Products Laboratory. Part III gives a summary of the chemical, 

 physical, and toxic properties of creosotes as ,a whole. Part IV is 

 concerned entirely with methods of testing and specifications. 



The author wishes gratefully to acknowledge the services of Messrs. 

 L. E. Cover and J. P. Mehlig, formerly assistant chemists in forest 

 products. Much of the routine work described in Part II was done 

 by one or the other of these gentlemen. 



