228 



PRODnCTS DERIVKD PROM TURPENTIKES. 



a fine sieve. Lastly the slight quantity of oil remaining may be 

 driven o£f by heating the resin in an open pan. 



There are now many improved methods of distillation, ■which, 

 however, require special elaborate apparatus. One of these is 

 represented in Fig. 70. The first purification of the crude oleo- 



Fig. 70. 



Apparatus for distilling turpentine. 

 S isa slightly enlarged section on SS in A. 



resin is effected in the boiler h, which has a moveable lid and 

 through which runs, a steam-coil c. At o is an orifice with a grat- 



