ENDLESS CHAINS 



93 



means of an endless sprocket chain working on a shaft at the bot- 

 tom and top of the stack, and bearing fixed dogs at intervals to 

 hold the trays. A crank on the lower shaft served to move the 

 column of trays, and the chain returned on the outside of the 

 stack. 



"The Williams evaporator works endless chains wholly inside 

 the stack, and the trays are brought back to the feeding door, 



Fig. 20. Same as Fig. 19, rear view. Coal shed on the left. 



where they are removed. This saves running up and down stairs 

 with the trays, which is a drawback in the towers already de- 

 scribed, and it allows the operator to inspect any tray of fruit 



at will by turning the crank and bringing it back to the door. 



* * # 



"A tower dryer constructed upon a different principle is the 

 Automatic, made in Philadelphia. In this machine the trays 

 themselves fit upon one another and form the stack. The entire 



