6 CONTENTS. 



Tabulation of results Continued. Page. : 



8. Summary of refining experiments with column stills showing the 



relation between the percentage of turpentine in the distillate and 



the composition of the turpentine 66 ! 



9. Refining experiments with a pot still, showing the percentage of turpen- 



tine in the distillate and the composition of the turpentine 67 ' 



10. Summary of Table 9, showing constants of turpentine samples taken 



during the progress of distillation and the percentage of turpentine 



in the distillate 681 



11. Detailed opinions of the workmen on the varnishes used 69 



ILLUSTRATIONS. 



Page. 

 FIG. 1. A simple periodic column still with chambers containing broken rock. . 24 



2. A periodic column still with the chambers separated by hooded plates. . 25 



3. An ordinary continuous beer still used for turpentine distillation 26 



4. A continuous still with hooded plates 26 



