2 BULLETIN 1036, U. S. DEPARTMENT OE AGRICULTURE. 
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. 
