CLARIFICATION 51 



time when prices were good, and formed no small part 

 of the raw material of some British refineries. 



In our West Indian Colonies the process of clarifica- 

 tion was carried on, and still continues in some places, 

 in a similar but much superior fashion. The " Copper 

 Wall" was universal sixty years ago in the West Indies. 

 It is simply a row of copper basins, with a blazing fire 

 underneath them going the whole length of the row 

 and then up the chimney. The juice, much purer 

 than that from the powerful modern mills with all 

 their appliances, contained nevertheless much albumin- 

 ous and gummy matter which must be removed. The 

 copper wall combined clarification and crystallization. 

 In the first copper milk of lime was added, and the scum 

 skimmed off ; in the succeeding coppers, to which the 

 juice was ladled from No. 1, a further skimming or 

 brushing took place, and when the juice reached the 

 last of the six coppers it had become thick enough and 

 pure enough to crystallize when cool into an excellent 

 raw sugar, called muscovado, the principal raw material 

 of the British sugar refiner sixty years ago. 



But new appliances, in the course of time, took the 

 place of the copper wall. The vacuum pan was invented 

 for carrying out a more perfect kind of crystallization. 

 Then came the European beetroot industry, which 

 introduced many varieties of clarification and defecation. 

 Capable men took up the subject and gradually developed 

 a really scientific system of dealing with sugar juice. 

 Lime was still the basis of the system, but it was no 

 longer used in a haphazard or rule-of-thumb manner. 

 Lime is absolutely necessary, especially with cane 

 juice, which is naturally acid ; but though it removes 

 impurities it is liable to create more than it removes 

 by forming lime compounds very detrimental to the 

 subsequent crystallization. The beetroot factories 



