4 BULLETIN 921, U. S. DEPARTMENT OF AGRICULTURE. 
EXPERIMENT 1. • 
Type of juice : Crusher juice, about 40 per cent extraction. 
Filtering material : Infusorial earth from Lompoc, Calif. 
Amount of filtering material used : 11 pounds to 200 gallons of juice. 
Result: 1,065 gallons of juice were filtered with a pressure not exceeding 40 
pounds, forming a very hard, firm press cake. 
Experiment 2. 
Type of juice : Crusher juice, about 40 per cent extraction. 
Filtering material : Infusorial earth from State of Washington. 
Amount of filtering material used : 18 pounds to 200 gallons of juice. 
Result : 1,000 gallons of juice filtered rapidly, leaving a firm, well-formed press 
cake. The filtered juice was bright and clear. 
Experiment 3. 
Type of juice : Whole mill dilute juice. 
Filtering material : Infusorial earth from Lompoc, Calif. 
Amount of filtering material used: 10 pounds to 200 gallons of juice. 
Course of filtration : 
Time of 
filtration. Pressure. 
First 200 gallons 15 minutes. 10 pounds. 
Second 200 gallons 15 minutes. 20 pounds. 
Third 200 gallons 25 minutes. 30 pounds. 
Fourth 200 gallons 40 minutes. 40 pounds. 
Fifth 200 gallons 45 minutes. 50 pounds. 
Sixth 200 gallons 1 hour 5 minutes. 60 pounds. 
1, 200 gallons 3 hours 25 minutes. 
Result : The juice running from the press in this experiment was clear and 
brilliant, free from dirt, dregs, or sediment. It was necessary only to evapo- 
rate it to obtain a high-grade sirup. The press cake was very hard with the 
exception of the upper corners, which were a little soft. 
Experiment 4. 
Type of juice : Whole mill, dilute juice. 
Filtering material : Infusorial earth from Lompoc, Calif. 
Amount of filtering material used : 12 pounds to 200 gallons of juice. 
Course of filtration : 
Time of filtration. 
First 200 gallons 15 minutes. 
Second 200 gallons 15 minutes. 
Third 200 gallons 15 minutes. 
Fourth 200 gallons 30 minutes. 
Fifth 200 gallons 45 minutes. 
1, 000 gallons. 2 hours. 
Maximum pressure, 50 pounds. 
Result: During the entire filtration the juice filtered freely and clearly, slow- 
ing up somewhat, however, as the frames became filled, The resulting press 
cake was very firm, each frame being completely filled. 
