34^ OITMISTKY APPLIED TO AGKICULTUKK, 



tion, and renewing' the alcohol till the liquor passed off 

 perfectly clear from the point of the mould ; this alcohol 

 I redistilled,, to employ in new operations. 



I abandoned this method of bleaching sugar for the fol- 

 lowing reasons. 



1. Notwithstanding all the precautions 1 tooky I lost half 

 a kilogramme (a little more than a pound) of alcohol for 

 each loaf of ten pounds' weight. 



2. The loaves of sugar, though well dried in the stove^ 

 always preserved a slight odor, which became more sensi- 

 ble after their having been confined in the papers and 

 transported. 



3. The price of alcohol of this degree of concentration, 

 rendered the refining by alcohol as expensive as that of 

 clay. 



Some very skilful chymists propose to supply the use 

 of clay by that of sirup ; theory is in favor of this method, 

 but experiment contradicts it. 



In the first place, in order that the sirup may be em- 

 ployed with success, it is necessary that it should be white, 

 and of course that it should be made by saturating water 

 with very white sugar. The water which is disengaged 

 from the clay produces a sirup in passing through the 

 layer of sugar with which the loaves are covered ; there 

 is, therefore, no advantage to be derived from the use of 

 sirup on account of its containing sugar, and the process 

 is less economical than claying, inasmuch as both time 

 and fuel * are required for making the sirup, whilst in 

 claying it is produced by the process itself. 



However, as the theory is seducing, I tried this method, 

 and the following statement exhibits the results. 



I prepared a quantity of sirup at 30° t ( ::= 1.261) of 

 concentration, which I poured upon the smoothed surface 

 of the loaves till they were covered with it ; the following 

 day the sirup had penetrated into the mass, which was 

 sensibly whitened by it. I repeated the operation at inter- 

 vals of four hours, till the sirup passed off through the 

 point of the mould clear ; this did not take place till the 



* I say fuel, because water will not dissolve so much sugar by re- 

 maining upon it at the temperature of the atmosphere, but that it will 

 take up still more in filtrating through it ; so as to increase in con- 

 centration .3° or 4°. 



ti This is the point to which it is necessary to carry it, that it may 

 not dissolve the sugar when cold. 



