44 



CHAPTER II. 



RASPING THE BEETS. 



The first idea of the famous Achard when in search of 

 the best mode of extracting the sugar from beets, was to 

 boil them and reduce them to paste, but he soon found in- 

 superable difficulties in the way of this process. The 

 simple pressure without rasping has been repeatedly tri- 

 ed, and recently again by an improved press, and the rasp 

 is as yet the only effectual mode employed, and too much 

 care cannot be used in having this operation well done, as 

 on it depends, in a great measure, the more or less sugar 

 that is obtained. There is a great diversity in the con- 

 struction of this machine, but the cylindrical rasp of Mo- 

 lard appears to have the preference : the cylinder is of cast 

 iron, into which 120 saw plates are inserted ; as a descrip- 

 tion of this would probably be unintelligible without a re- 

 presentation of it by an engraving, I will not attempt it. A 

 man presses the beets enclosed in a box against the cir- 

 cumference of the cylinder, another workman on the oppo- 

 site side of the machine removes the pulp, and with the la 

 die with which he removes it fills bags as we shall more 

 particularly explain in the next chapter, from 80 to 100 

 lbs of beet are reduced to pulp in one minute. 



The rasping requires, as well as every other operation 

 of this manufacture, great activity, and as much as pos- 

 sible the rasping more beets than are immediately wanted 

 must be avoided, as a prejudicial change takes place in the 

 pulp from a quarter to a half hour at most after it is pro- 

 duced ; a blackish color, which gradually increases is the 

 indication of this change. It is therefore prudent that no 

 more should be rasped than can be immediately pressed. 



