ILLUSTRATIONS. 



Pag<\ 

 FIG. 1. Hempel column II 



2. Typical curves showing boiling points, specific gravities, and indices 



of refraction of a gum turpentine ] 3 



3. Curves illustrating theory of fractional distillation 14 



4. Comparison of fractionation obtained in steam distillation with a Geer 



dephlegmator and without a dephlegmator 18 



5. Comparison of fractionation obtained in direct distillation with a Le 



Bel-Henninger column and without a dephlegmator 19 



6. Comparison of fractionation obtained by steam distillation with a Geer 



dephlegmator and direct distillation with a Le Bel-Henninger de- 

 phlegmator 20 



7. Comparison of fractionation obtained by (1) steam distillation with a 



Geer dephlegmator, (2) direct distillation with a Le Bel-Henninger 

 dephlegmator, and (3) direct distillation without a dephlegmator. . 21 



8. Comparison of fractionation obtained by direct distillation with a Le 



Bel-Henninger dephlegmator and steam distillation with a Geer 

 dephlegmator 22 



9. Effect of boiling with water (steam distillation) and of boiling without 



water (direct distillation) on the specific gravity and index of re- 

 fraction of crude wood turpentine . 23 



10. Effect of boiling with water (steam distillation) and of boiling without 



water (direct distillation) on the specific gravity and index of re- 

 fraction of refined wood turpentine 23 



11. Alteration in physical properties of a crude wood turpentine due to 



direct distillation 24 



12. Alteration in physical properties of a crude wood turpentine due to 



steam distillation 25 



13. Alteration in physical properties of a gum turpentine due to direct 



distillation 26 



14. Comparison of fractionation with Le Bel-Henninger and Hempel 



column dephlegmators 27 



15. Boiling cap section 



16. Pressure regulator 29 



. 17. Separator 30 



18. Speed indicator 31 



19. Calibration curve for crude turpentine speed indicator 



20. General arrangement of apparatus for refining crude turpentine 33 



21. Boiling point, specific gravity, and index of refraction curves for crude 



turpentine No. 1, untreated 34 



22. Boiling point, specific gravity, and index of refraction curves for crude 



turpentine No. 2, after treatment with caustic soda solution 35 



23. Boiling point, specific gravity, and index of refraction curves for 



"heads" obtained in refining of crude turpentine No. 1 36 



5 



