UNITED STATES DEPARTMENT OF AGRICULTURE 



BULLETIN No. 508 



Contribution from the Forest Service 

 HENRY S. GRAVES, Forester 



J^^<^^t^ 



Washington, D. C. 



PROFESSIONAL PAPER 



March 6, 1917 



YIELDS FROM THE DESTRUCTIVE DISTILLATION 

 OF CERTAIN HARDWOODS. 



SECOND PROGRESS REPORT. 



By R. G. Palmee, Chemist in Forest Products. 



CONTENTS. 



Purpose of experiment 



Plan of investigation 



Method of recording data 



Yields on per cent weight basis. 



Yields per cord 



Pyroligneous acid, tar, and charcoal . 

 Commercial distillation 



PURPOSE OF EXPERIMENTS. 



The object of the investigations reported in this bulletin and in 

 Bulletin 129, to which this is supplementary, M^as to determine the 

 relative value of the various hardwoods commonly used for de- 

 structive distillation, and of the different forms of material, such as 

 bodywood, limbs, and slabs. The experiments were carried on at 

 the Forest Products Laboratory, maintained at Madison, Wis., in 

 cooperation with the University of Wisconsin. The standard 

 species — beech, birch, and hard maple — were included in the labora- 

 tory tests so as to make the results on other species comparable with 

 them and hence commercially applicable. Bulletin 129 gives the 

 yields for these three standard species, and, in addition, red gum, 

 chestnut, hickory, white oak, and tupelo. The present bulletin gives 

 the yields for white elm, slippery elm, silver maple, green ash, blue 

 ash, yellow ash, chestnut oak, tanbark oak, California black oak, 

 Louisiana swamp oak,^ and eucalyptus. 



The results here reported are of most value when compared with 

 laboratory distillations of species whose yields in commercial prac- 



1 " Swamp oak " was a mixture of laurel, post, water, willow, Spanish, and cow oaks, 

 usually growing in mixed stands. Acknowledgment is made of the assistance of Mr. H. 

 Cloukey in analyzing some of the distillates. 



Note. — This bulletin gives the results of experiments in destructive distillation of 

 hardwoods and is of interest to manufacturers of by-products. 

 70252° — Bull. 508—17 



