YIELDS FROM DISTILLATION OF CERTAIN HARDWOODS. 
Table 1. — Sample data sheet. 
Shipment No. 197. 
Sample Nos. 21 and 22. 
January 14, 1913. 
Actual weight of charge 69.86 pounds. 
Dry weight of charge 63.10 pounds. 
Project No. 152. 
Run No. 97. 
Birch slab wood. 
10 per cent to 14 per cent bark. 
Time. 
Temperature. 
IP 
Remarks. 
Tube 
No. 1. 
Tube 
No. 5. 
January 13. 
•a 
°C. 
20 
180 
220 
246 
263 
278 
291 
305 
318 
325 
351 
370 
378 
379 
376 
284 
' 50 
c. c. 
Retort charged; gas on one 
Gas on full. 
Gas off. 
Maximum temperature. 
-half. 
8.20 a. m . . 
January 14- 
234 
280 
303 
312 
317 
322 
329 
336 
342 
342 
344 
341 
339 
337 
282 
3,200 
4,200 
5,700 
6,700 
7,700 
8,700 
9,700 
10, 700 
11,700 
12, 700 
13, 200 
13, 500 
10 a. m 
10.50 a. m 
11.06 a. m 
11.16 a. m 
11.22 a. m 
11.27 a. m 
11 33 a. m 
11.40 a. m 
11.51 a. rn 
12.06 a. m 
12 11 a. m 
1 50 a. m. . 
14,000 
14, 200 
January 15. 
Total distillate = 32.83 pounds. 
COLLECTION AND ANALYSIS OF PRODUCTS. 
A typical data sheet is shown in Table 1 . The time and tempera- 
tures were read as every liter or half liter of distillate was collected. 
In a few distillations separate titrations for acetic acid were made 
on the first several fractions of one-half liter or one liter each, but in 
general all the distillate was mixed for analysis. 1 The distillate was 
allowed to settle for at least 24 hours. At the end of that time the tar 
and pyroligneous acid were separated by decantation, and the vol- 
ume and weight of each determined. The charcoal was allowed to 
cool in the retort over night, and was weighed after separation from 
the "tar coke." Tar coke refers to the material occurring in the 
retort that was clearly a residue from the distillation of tar. This 
was weighed separately. The gas was computed by difference, and 
no determination of its composition was made.. 
PYROLIGNEOUS ACID. 
The pyroligneous acid was analyzed by the methods described by 
Klar 2 for the determination of acetic acid, wood alcohol, and dis- 
i The acetic acid in that part of the distillate (consisting usually of water) which came over before true 
destructive distillation began amounted to from 8 to 10 per cent of the total acetic acid; the alcohol in the 
same part amounted to about 1 per cent of the total alcohol. The volatile acids obtained at temperatures 
below the point at which the wood begins to distill destructively, say 280° C, must have an origin differ- 
ent from that of the acid obtained during the destructive distillation. It is probably formed by action of 
the water on the wood fiber at high temperatures similarly to the acid obtained by hydrolysis as reported 
by Cross (Dissertation, Gottingen, 1910). 
2 Technologie der Holzverkohlung, p. 337. 
