K. J. EBERT ON BEET-SUGAR. 399 



filled, the air-valve, and to open both the steam-valves on it to let 

 the steam enter the hollow bottom spaee. The time when the 

 lime is to be added depends much on the quality of the beets ; a 

 thermometer must be at hand, however, and it might be well to 

 appoint it at 60° to 65° E., that is, when the temperature of the 

 boiling fluid has attained to that degree. 



During the adding of Lime. — When this is done the steam- valves 

 must be closed, and the necessary quantity of the lime dissolved 

 in water quickly added, stirring it well into the fluid. After this 

 the steam- valve is only partially, but the air-valve fully opened, 

 and the foam now forming on the surface of the juice pushed back 

 to observe the action of the fluid. Soon the albuminous flakes 

 will begin to rise ; the limy foam begins to burst and give way be- 

 fore the green scum. More and more this will concentrate, look 

 dry, fleecy, and light. Finally, some parts of it will expand them- 

 selves considerably, and j uice-fountains burst through them. Then 

 the boiling liquid is defecated. 



In regard to the quantity of lime to be taken, f to 1^ pounds 

 of it would be quite sufficient for 100 pounds of beets. 



The sediments in the kettle and the foam remaining can be put 

 into bags and pressed out again, as they may contain sugar matter 

 and sufficient juice to pay for the trouble. 



Treatment of the defecated Juice. 



Clear and transparent, this must be directly taken to the " evap- 

 orating pan," or, which is better, conducted to it by means of a 

 pipe. Before it enters, it answers well to let it pass through a fil- 

 ter, in order to free it of its lime parts. These filters may be con- 

 structed from a tin or copper vessel, whose perforated bottom is 

 covered with woolen or linen cloth, and a thin layer of bone-black. 

 Some also neutralize the lime by the application of carbonic acid. 



The Concentration^ Filtration, and the preparation of the ^^ Spodium." 



The object of these actions is to remove the superfluous water 

 mixed with the sugar of the juice, effected by a continued evapo- 

 rating process and a filtering over animal coal. The first reduces 

 the quantity of the juice to one ninth of its original volume ; and 

 as this can not be done by one, it must be so by a second repeated 

 evaporation, and the latter takes place after each of these. 



The evajjorating aj^paratus consists mainly of a copper vessel 

 resting upon a wooden stand, of a depth equal to about the fourth 

 part of its diameter, closed by a wooden lid, leaving only a semi- 

 circular opening that also can be closed by a hinge cover, and of 

 a conduit, through which the steam formed by the boiling may 

 escape. Close by this there is a pipe, extending through the lid, 

 with a faucet to let the defecated juice pass into, and another one 

 at the opposite side of the bottom to let the evaporated off. One 

 of the most important inventions of late years for the purpose of 



