294 PURIFICATION OF THE JUICE OF THE BEET ROOT. 
the removal of all the coagulable matters by the use of sulphate of 
lime, the saccharine juice be agitated in the cold, or at a temperature 
under ebullition, with hydrated sesqui-oxide of iron, the liquor passes 
through the filter entirely decolorized, and purified moreover from 
almost all traces of foreign substances. In addition to this, the rea- 
gent in question, by its well-known property of absorbing alkaline and 
and earthy salts, removes any small amount of sulphate of lime that 
may remain in solution. In this manner, the juice, which after the 
first purification by sulphate of lime, reduces nitrate of silver, bin- 
oxide of mercury, &c., becomes without action on these bodies after 
its treatment with the peroxide of iron. 
Under normal conditions the juice thus purified, is perfectly 
neutral to test-papers; and it may be kept in contact with the air for 
several days without exhibiting the slightest change or coloration. 
This is conclusive as to the fact that all matters capable of acting as a 
ferment, have been removed. It boils easily, and remains uncolored 
under the action of heat. When brought to the proper consistency, 
the syrup possesses only the pale yellowish tint of all pure syrups. 
Its taste is pleasant, and altogether free from that disagreeable 
saline flavour that is found in ordinary beet-root syrups; and in 
addition to this, it preserves a remarkable clearness and fluidity. 
It also crystallizes readily, yielding colorless crystals. Finally, as a 
conclusive test of the degree of purification obtained by this process, 
the prepared syrup, brought down to 30° of the areometer by the 
addition of a proper quantity of water, may be mixed with a large 
excess of alcohol at 90° without exhibiting any turbidness or yielding 
the slightest deposit, even after the lapse of several days. Besides 
which, it does not retain the least trace of iron. 
The fabrication of beet-root sugar becomes reduced, consequently, 
to the following simple processes. The saccharine juice is first to be 
warmed in a caldron or other convenient vessel with a small quantity 
(a few thousandths) of sulphate of lime. Common or native gypsum 
answers best for this purpose. The coagulated matters then collect 
into a thick scum. Secondly, the clear juice, thus partly purified, is 
to be agitated with some peroxide of iron. Thirdly, after the separa- 
tion of this latter, the juice has only to be subjected to the necessary 
evaporation. The sulphate of lime and the peroxide of iron remove 
all foreign matters from the sugar, and yield it nothing in return. 
