AMERICAN BEET SUGAR. 35 



to the water outside, till there remains 7 per cent, in the cell and 7 per cent, in the 

 water ; this water, which now is a dilute juice, is forced by gravity into the next 

 cell. Having been heated in transit to 80 C., there is again an interchanging of 

 sugar from the sugar cell to the juice ; this time the water admitted having already 

 7 per cent, sugar will extract but half of the difference between the sugar in it 

 and in the beet, and there will be 10.5 per cent, sugar in both water and slices ; 

 this is again forced over to the next cell of fresh slices, and again there is an in- 

 terchanging or evening up, and there will be 12.25 P er cent, sugar in the juice ; 

 and so on till this water has passed over eight to ten cells, when it becomes nearly 

 as concentrated as the beet juice. 



To go back to the first cell, in this we had slices with 7 per cent, sugar and 7 

 per cent, sugar in the water ; this water was forced over to the next cell by means 

 of fresh water ; this water again eliminated half of the sugar, and there remained 

 but 3^ per cent, sugar ; when the third cell was filled it was done by forcing 

 water in cell No. i, which in turn being connected, forced the liquid contents of 

 No. 2 into No. 3, and so on. This fresh water that for the third time has been 

 admitted to cell No. i again extracts half of the sugar, leaving 1.75 per cent sugar 

 in both water and slices. This process is carried on till there remains from 0.5 to 

 0.25 per cent, sugar in the slices, when they are emptied by a door at the bottom 

 of the cell, when the cell is refilled with fresh slices to be again subjected to the 

 same process. 



CARBONATION PROCESS. The juice when sufficiently concentrated is drawn 

 off by measure, taking enough to extract the sugar without too great a dilution ; 

 this is accurately measured and a record kept of the time, number of cell, and 

 density. This juice flows by gravity into a heater (calorisator) where it is heated 

 to 190 Fah. This is important, as it is necessary to coagulate all albuminoids 

 before the presence of lime. From the "heater " the juice flows to the " carbon- 

 ator " (a large closed tank with suitable valves and appliances for admitting the 

 juice, lime, carbonic acid, etc.). To the heated juice there is admitted from 2 to 3 

 per cent of lime in the form of milk of lime (22B.); this lime combines with the 

 greater part of the impurities and forms an insoluble precipitate. The action of 

 the lime is complex, and it is not necessary to go into the minutiae in an article of 

 this kind. 



THE USE OF CARBONIC ACID GAS. The lime also combines with the sugar, 

 forming a sucrate of lime, which if not decomposed would be lost during filtra- 

 tion; this is done by injecting carbonic acid gas, which is made in burning the 

 lime used in clarification, forming an insoluble precipitate of carbonate of lime. 

 Just enough gas is admitted to break up this combination of lime and sugar ; care 

 is taken not to carry the operation too far, as after the sucrate of lime is de- 

 stroyed, the carbonic acid attacks other compounds of lime, and in time would 

 liberate all the impurities again. The process is closely watched, and samples 

 are taken every few seconds as the operation approaches completion. The 

 samples are taken in a test tube, the proper point at which to stop the flow of 

 carbonic acid gas is shown by the formation of a granular precipitate, showing 

 clear liquor between the particles; the gas is then instantly shut off, a test 

 sample is sent to a table near by, where a chemist assistant is stationed, and the 

 per cent, of lime in the juice determined by a standard acid. 



