8 







because those promoting the enterprises have been able to profit by 

 the mistakes of their predecessors. Yet many operators have failed! , 

 mainly because they nad not familiarized themselves with the fun- 

 damental principles controlling the successful construction and opera- 

 tion of a plant. 



The figures on pages 6 and 7 are not intended to compare yields 

 by destructive and steam distillation from the same grade of wood, 

 but simply the yields obtained by the two methods under actual 

 conditions, where, in point of fact, very different grades of wood 

 are used. 



There is but scanty published information on the properties of the 

 turpentines produced by these two processes in America, or on their 

 actual value in the paint and varnish business. Uj) to the present 

 these turpentines are merely competitors of "gum spirits." 



Approved : 



JAMES WILSON, 



Secretary of Agriculture. 



WASHINGTON, D. C., August 19, 1907. 



[Cir. 114] 



O 



