YIELDS FROM DISTILLATION OF CERTAIN HARDWOODS. 



15 



I The value of the two products (alcohol and acetate) from hickory 

 is 18 per cent greater than the standard chosen for the comparison. 

 Of the other species, oak from Indiana is the only one which falls 

 above 90 per cent; with all the others, except chestnut, the average 

 yield from heartwood and slab wood is ubove 80 per cent. 



Of equal interest to these relative values based upon species are 

 the relative values of the different forms of wood from the same 

 species. These relations are shown in Table 8, in which the value 

 of heartwood in each case is taken as 100 per cent. A number of 

 species show a higher value for slabs than for heartwood. The slabs 

 of Indiana beech, Wisconsin birch, Pennsylvania beech, and Arkansas 

 oak are from 2 to 5 per cent higher that the heartwood, while the 

 limbs of the two species tested, chestnut and tupelo, are about 15 

 per cent higher than heartwood. These results are based upon 

 equal weights of the several forms of material compared. 



TABLE 8. Relative values of commercial alcohol and acetate from equal weights of various 



forms of material. 

 [Heartwood =100 per cent.] 



PYROLIGNEOUS ACID, TAR, AND CHARCOAL. 



The average yields of pyroligneous acid, tar, and charcoal from 

 the various forms of material, expressed in pounds per cord for each 

 species, are given in Table 9. Although the yields of these products, 

 especially of the last two, are directly affected by the maximum tem- 

 peratures of distillation, and are therefore not as accurate as the 

 alcohol and acetate yields, some conclusions of interest can be drawn 

 from them. The yields of pyroligneous acid are of interest mainly 

 in connection with the cost of refining the products from a cord of 

 wood. (See footnote on p. 14.) 



The average commercial yield of charcoal from a cord of beech, 

 birch, and maple is about 50 bushels or (at 20 pounds, the usual 

 weight per bushel) 1,000 pounds; the average yield from the heart- 

 wood of the three species by the experimental method is 1,378 pounds 

 per cord. This large difference is probably due chiefly to the low 

 maximum temperatures of distillation, resulting in a charcoal with 

 a high amount of volatile matter. Charcoal of this composition 

 would probably be satisfactory as a fuel for domestic use, but where 



