THE EXTRACTION OF THE JUICE BY MILLS 



189 



The results may be interpreted as favouring a high speed and a thin 

 blanket of material. 



4. Under pressures up to 60 lbs. per sq. in. it was found that the volume 

 occupied by bagasse varied inversely as the 2 • 5th root of the pressure, 

 or s\Tnbolically V P'^ = constant, where V is the volume of the bagasse 

 and P is the pressure. If the bagasse be pressed in a cylinder, H, the height 

 of the column of bagasse under pressure may be substituted for V. Data 

 of an experiment are given below, the results being also expressed as a 

 curve in Fig. 77. 



Height of 0'22I lb. Bagasse, containing 32 '6 per cent. Fibre, on a Surface 

 of8'43 So. Ins., corresponding to 100,000 lbs. Cane containing 12 per cent. 

 Fibre per Hour, at a Surface Speed in Rollers of 25 ft. per Minute in a 78-iN. 

 Mill, up to Pressures of 60 lbs. per so. in. 



5. At higher pressures, 1,000 lbs. per sq. in. and upwards, the volume 

 of bagasse varied inversely as the 5th root of the pressure, or symbolically 

 H P-^ = constant. Data of an experiment are given below, the results 

 being also expressed as a curve in Fig. 78. 



0.397 lbs. Bagasse corresponding to 120,000 lbs. of 12 per cent. Fibre Cane 

 per hour in 78-IN. Mill, at a Surface Speed of 25 ft. per min. 



At higher pressures the volume of juice expressed from chopped cane 

 varied as the twentieth root of the pressure, or s3'mbolically / P"*' = con- 

 stant, where / is the volume of the juice expressed.* 



*In my original publication I gave the volume as varying with the twelfth root, 

 results Bolk' observed that the twentieth root gives a much more constant value. 



In commenting on these 



