soda and it was difficult to obtain a clear distillate. 

 Distillation of turpentine was slower and the yield 

 was low (41 gals, per cord), due to retention of 

 volatile oil by the unsaponified rosin remaining in 

 the chips. This was apparent from the recovery 

 of an additional 2.9 gals, per cord during the soda 

 cook. A decided advantage was noticed, however, 

 in the decreased attack of the lignocellulose by the 

 weaker alkali, the amount dissolved being only 

 11.4 per cent of the actual wood. The chips were 

 finally cooked in a 2.3 per cent caustic soda solu- 

 tion, and kept at 100 pounds pressure for 2fhours. 

 Disintegration was hardly thorough enough, as the 

 pulp retained the chip form and required long treat- 

 ment in the beater before the fibres would felt 

 properly. This explains the high yield of 49.7 per 

 cent. 



In Experiment 8 the resinous chips were sub- 

 mitted to a single treatment for pulp to provide 

 a standard for the comparison of fibres. A 4.8 per 

 cent solution of NaOH was used, containing an 

 amount of Na20 equal to 18.5 per cent of the 

 weight of the resinous wood. With the intention 

 of also making this run a quantitative determina- 

 tion of turpentine the pressure was first held at 

 about 30 pounds for 3 hours in order to distil 

 over the turpentine at a moderate temperature. 

 Unfortunately, a slight leak developed in the top 

 of the digester and the recovery of volatile oils 

 amounted to only 32.6 gals, per cord. After most 

 of the turpentine had been removed, the pressure 

 was raised to 100 pounds and cooking was continued 

 for 3 hours more. The yield of pulp was 44.2 per 

 cent and the fibre was long and uniform, although 

 apparently no different from the pulp obtained in 

 certain of the two-stage operations. 



36 



