36 Sorghum Hand Book. 



In case the filter becomes stopped up the fluid contents may be removed by a stop- 

 cock, which is inserted into the open space at the bottom, when a pail or so of water 

 will wash out the accumulated impurities. This filter should be thoroughly washed 

 with water when not in use, and a little lime should be added to the last washings to 

 avoid fermentation. 



DEFECATION WITH LIME, 



Lime is an important aid to defecation. It is not used to neutralize the acids, 

 except incidentally. The acid is expelled in a great measure by heat. Its effect is to 

 coagulate and separate a class of impurities which heat alone fails to remove. It pre- 

 vents the development of that clotted substance in the syrup called jelly. It gives the 

 syrup a clear, amber color, entirely different from that dull, milky or cloudy appear-, 

 ance which is nearly always observed. But in using lime the utmost care must be 

 employed. It should be stirred up with water and allowed to stand a minute or two 

 until the heavy particles subside and the fluid acquires about the color and consistency 

 of new milk. Then add to the cold juice in the tank or receiver, at the rate of about 

 two or three gills to every fifty gallons of juice, and stir it thoroughly until it is per- 

 fectly incorporated with the whole. If you have litmus paper, (a little roll, enough for 

 • a whole season costs but twenty-five cents,) dip a narrow strip into the juice before 

 adding the lime. It will turn the paper red. After adding the lime, dip the other end 

 of the same strip into the juice and compare the two ends. If the color produced by 

 the last test is a little less red than the first, bordering more on pink or purple, the 

 lime has produced an effect and no more is needed. If, however, you can discover no 

 difference in the hue of the paper, a little more lime may be added and the test re- 

 peated. We hav^ seen juice that did not indicate the presence of free acid, l;he litmus 

 paper not being changed ; but this is rare ; acid is almost always indicated. We think 

 if you use lime in this prudent, cautious way, you will find great advantage in it. But 

 if you allow " the boys" to have a tub of whitewash, with permission to stir it up from 

 the bottom and immediately bale in any quantity that their fancy or indifference may 

 permit, you will see nothing but its mischievous effects, and probably join with' others 

 in the indiscriminate condemnation of the whole thing. It is a good plan to mix the 

 charge of lime with a bucket of juice before putting it into the receiver, and delay 

 adding the lime until just before the juice goes into the pan, in order to secure the full 

 combined defecating effect of both the lime and. heat. Remember that coagulum, if 

 properly separated and managed, locks up and brings off the insoluble floating par- 

 ticles which are also contained in the juice. It operates precisely like eggs, milk, 

 blood, and other substances which are frequently added for the purpose of clarifying, 

 and the aim of the operator is not simply to remove this coagulated matter, but -also 

 the insoluble impurities with it. As the amount of lime which is approximately 

 correct will soon be known, the additions at first may be more rapid than at the close; 

 but, as the point of neutralization is approached, the greatest care should be exercised 

 to avoid an excess. Should too much lime be accidentally added, a little more fresh 

 juice may be brought into the defecator, although with care this will very rarely be 

 necessary. 



Many experiments have been made for the purpose of learning at what temi^er- 

 ature the lime should be added, and there appears to be no difference whether the lime 

 ■ is added to the juice at the ordinary temperature, or at any point under boiling. Owing 

 to the possibility that the acids of the juice may cause the inversion of some of the 

 sugar after the heating is begun, also in order to have ample time for adding the proper 

 amount of lime before the boiling point is reached, it would seem to be desirable to add 

 the lime as soon as possible after turning on the heat. If an excess of lime is used, 

 it will result in giving a darker color to the juice and to the syrup produced from if. 



After having withdrawn the heat, the contents of the defecator are left at rest for 

 from fifteen to twenty minutes, after which the scum may be carefully removed by a 

 large skimmer, pierced with holes not over one-sixteenth of an inch in diameter, and 

 this scum may be emptied into a gutter upon one side of the defecator, by which it 

 may run to the scum tank for future treatment. 



It has been the practice of many to draw the contents of the defecator immedi- 

 ately after skimming into settling tanks, where it is allowed to stand, as in the defe- 

 cator; but it would seem desirable to have two or more defecators in use, so that they 

 may take the place of settling tanks, and thus avoid the necessity of disturbing the 

 juice during the subsidence of the sediment. 



