26 SUPPLEMENT. 
three gills of blood, or the whites of eight eggs, well beaten. If you 
have neither, two pints of milk will answer, but not so well. Add six 
tablespoonsful of milk of lime previously prepared, and stirred before 
using. Add about a gallon of juice, and stir the whole thoroughly 
together. 
Now dip into one of the tubs of unmixed juice a small strip of the 
blue litmus paper. It will immediately turn red, more or less vivid in 
proportion to the acidity of the juice. Lay the strip of litmus paper 
aside, and add to kettle No. 1 about nineteen gallons more of juice ; 
stir the whole. Then dip the strip of reddened litmus paper into the 
kettle. If it again become blue, the acid is entirely neutralized. If 
not, continue to stir in milk of lime in small quantities, and to test 
with the litmus paper, until its original blue color is restored. 
Now light a fire under kettle No.1. As the juice grows hot a 
thick scum will rise. Do not disturb it, but bring the juice to a boil. 
To be sure that it does boil, remove a little of the scum with the 
skimmer, and insert your thermometer. When it marks 215° Fahren- 
heit, and the scum begins to ro/l over, put out the fire immediately, or 
remove the kettle. Let it stand ten or fifteen minutes. Then care- 
fully remove the scum with the skimmer into a third pail. Then boil 
again. 
When the saccharometer marks 15° Beaumé in the boiling juice, 
extinguish the fire, or remove the kettle, and let it cool to 160° Fah- 
renheit, or cooler. Now stir in six more eggs well beaten, or two 
gills of blood, or one pint of milk. Omit the lime. Again bring it 
to a boil, again extinguish the fire, or remove the kettle; and, after 
standing ten minutes, remove the scum as before. Then ladle the clear 
juice into the bone black filter, (see preliminaries No. 3,) having first 
withdrawn the stopper, allowing the warm water to flow out below, 
as the juice is poured in above, being careful to keep the filter full of 
liquid. When the water below begins to run sweet, marking 3° 
Beaumé, throw away what has previously run out, and receive the re 
mainder in tub No. 3. 
We are now ready to continue evaporation, and it will be better to 
do so in smaller quantities, as in a shallower mass the concentration 
will be more rapid. Therefore, when about ten gallons have passed 
