EXTRACTION OF AROMA. 



25 



^ 



/I 



EJ 



^ 



water to pass continiiall}' through the condenser in an upward direc- 

 tion. The condenser is attached to the still by means of the union 

 joint, as illustrated. 



The tripod, G^ acts as a support for the condenser while the appa- 

 ratus is in operation and also while the still is being charged or dis- 

 charged. Under the bottom opening of the condenser is placed a 

 receiver, D, of copper, with a goose-neck siphon tube extending from 

 the bottom to within 2 inches of the top. On the side opposite the 

 siphon tube is fastened a small 

 brass spigot to admit the removal 

 of the oil from time to time. 



For the generation of steam, if 

 a source is not otherwise available, 

 a small boiler, such as is illus- 

 trated in figure 5, may be con- 

 veniently used. A small boiler, 

 yl, of light boiler iron fitted with 

 about a dozen flues is capped by 

 the cover, B. Other usual acces- 

 sories are attached, viz, water 

 gauge, C ;' pop valve, D ; water 

 gauge, E ; and steam outlet, F. 

 The boiler may be preferably set 

 upon a gasoline stove or an open- 

 fire stove or on a tripod with an 

 open fire beneath. The pop valve 

 maj^ be set at about 8 to 10 pounds, 

 no greater pressure being neces- 

 sars^- To replenish the water in 



the boiler a funnel tube attached to Fig. 5.— steam generator, a. Boiler ; n, 



the pop valve mav be used. Con- ^°'^^'' = ^' ^^^"^"^ s^"«^ ' ^' p^p ^^'^^ = ^• 



. \ . water gauge ; F, steam outlet. 



nection to the still is made most 



conveniently by the attachment of a short piece of rubber steam hose 

 to F, as this admits a ready detachment from the still when distilla- 

 tion is completed. A pressure of 5 to 10 pounds of steam is sufficient 

 for ordinary distillation. The size of the boiler may be slightly 

 increased if distillation is to be conducted on a larger scale. 



The boiler just described possesses efficiency enough to distill 

 charges of 75 to 150 pounds of herb. 



For distillation on a commercial scale a large, stationary, upright 

 boiler maj^ be installed for the generation of steam, or, if conven- 

 ient, steam may be taken from any high-pressure boiler which may 

 be in use for other purposes. The volume necessary being very 

 slight, indeed, is scarcely perceptible upon the steam gauge. 

 59647°— Bui. 195—10 4 



