THE EXTRACTION OF THE JUICE BY MILLS 



1S7 



When all these results are combined into their simplest form, that is 

 to sa}', when the cane is expressed as consisting of a soft part (pith) and a 

 hard part (rind and nodes), the average results appear as below : — 



86- s 

 ig-a 

 17-1 



86-4. 



13- 

 i8- 



12-7 



69- 1 



is.aoo 



/0.00c 



9.000 



In the analyses quoted 

 above the solids are ' ' refrac- 

 tive solids," the sugar is de- 

 termined by single polariza- 

 tion, and the purity is re- 

 fractive polarization purity. 

 The fibre is determined by 

 difference. 



These analyses, it must 

 be remembered, are quali- 

 fied by the personal e(juation 

 of the operator ; and abso- 

 lute separation into rind 

 and "pith " cannot be made, 

 since these divisions pass 

 gradually into each other. 

 The writer has also observed 

 as a general rule that a high 

 percentage of fibre is associ- 

 ated \\dth a high proportion 

 of rind tissue. 



The Behaviour of Cane 

 Fibre on Compression. — In 



the following section fibre is 

 used in its broadest sense 

 and refers to the insoluble 

 matter of the cane ; that is 

 to say to an indefinite mix- 

 ture of rind tissue and pith 

 tissue. As the process of 

 the extraction of juice is largely [one of exposing cane fibre to great 

 pressure, the writer made an experimental study^ of the behaviour 

 under pressure of cane fibre, represented by chopped cane and bv bagasse. 

 The experiments were made in the following manner : — The material 

 was placed in a cylindrical iron pot ^vith a perforated bottom. By 

 means of a tightly fitting plunger kno^vn pressures were applied to the 



X Tpoo 



■a.ooo 



/0OO 



He/o/r^: /nc/-e3 

 Fig. 78 



