114 Analysis of Feeding Materials [178-180 



corked up for analysis. Not that this analysis may be deferred 

 for any length of time j in fact, the portions of juice for different 

 operations must be measured out as soon as the quantities for 

 crude and woody fibre have been weighed from the pulp. 



178. When no further juice can be pressed out, loosen the 

 press, remove the bag, place it on a counterpoise clock glass, 

 and weigh on the ' rough ' balance. The next three weighings 

 must be performed as rapidly as possible, to prevent loss by 

 evaporation. They are as follows : 



Weigh out 50 grams of the pressed pulp for crude fibre. 



Weigh out 10 grams of the pressed pulp for woody fibre. 



Remove the rest of the pulp completely from the linen bag, 

 and weigh the bag whilst still moist. 



All these weighings may be performed on the rough 

 balance. 



Treat the two portions of pulp thus weighed out for crude 

 and woody fibre exactly as though they were samples of hay, 

 except that the washings with ether and alcohol are un- 

 necessary, as the pulp contains little or no colouring matter. 

 When these have been started, proceed at once to the analysis 

 of the juice. 



Analysis of the Juice 



179. The substances to be estimated in the juice are total 

 solids in the juice, soluble albuminoids, glucose, cane sugar, and 

 soluble ash. 



To save the trouble of weighing out separate portions, it is 

 usual to take the specific gravity of the juice and measure out 

 the amounts required, calculating the weights afterwards. 



180. Since the juice is apt to change in composition if kept 

 for any length of time, the immediate treatment of each portion 

 is first described, and the determination entered into more fully 



