238 



HOPS. 



Of the newer kilns only those will be mentioned that are 

 acknowledged as good by experts, and are therefore worthy 

 of recommendation. 



The Heijak kiln (Fig. 67), introduced in the "eighties," 

 differs from the older systems, and is specially designed for 

 treating large quantities of hops, the work of drying being 

 continuous. 



Pig. 67. — -The Heijak kiln (diagrammatic sketch). 



In the main this kiln consists of a large number of frames 

 (300) which slide on a spiral track placed round the interior 

 of a circular kiln, and are connected together by coupling- 

 hooks. To reduce friction, a number of small rollers are 

 arranged at intervals on the rails. A is an opening at the 



