270 



HOPS. 



acid fumes for two or three hours. According to Weiss, 

 ( about one-fifth of the total gas generated is retained by the 

 hops, whilst the remaining four-fifths escape through the 

 cowl. 



In place of sulphur the combustion of carbon bi-sulphide 

 has been proposed (Strebel). 



When the operation of sulphuring is finished, a current 

 of fresh air is allowed to pass through the hops for some 

 little time, and finally the hops are firmly compressed in 

 hydraulic presses, and packed in double pockets in metal 

 cases, metal-hned bins, or, more frequently, metal drums 

 (Fig. 7.5). 



Metal drums for storing hops (H. Schuldes, Saaz). 



Fig. 75. 



Drum with movable bottom and 

 lid, and three strengthening hoops, 

 for direct heavy pressing. 



Fig. 76. 



Drum with fixed bottom and mov- 

 able lid, for ballots. 



To facilitate emptying the drums the hops are sometimes 

 compressed into separate " cheeses "to fit the drum, or else 

 they are pressed into cylinders (ballots), which are then 

 covered with canvas and slipped into the outer drums, 

 which they are made, to fit. (Figs. 76, 77). In other cases 

 a special tool (borer) has to be employed for getting the hops 

 out of the drums, or a longitudinal, flanged joint (Fig. 78) 

 is provided, which enables the drum to be opened at the 



