370 PKOCEEDINGS OF THE SCIENTIFIC ASSOCIATION. 
men-oil and colouring matters and at the same time prevent 
any degenerating process from beginning through the action 
of the air on vegetable ferment or otherwise till ample time 
elapse for driving off the superfluous water and isolating the 
whole sugar in a state of purity. It was further stated that 
the next best mode of extraction, where the desiccation of 
the slices was undesirable, would be to macerate the slices as 
they fell in vessels containing water dosed appropriately with 
bisulphite of Lime. In either case the displacement of the 
sugar would be attained in the former methods entirely, and 
in the latter to extent of about nine-tenths of the whole but 
of somewhat inferior purity. Whenever the slightest impu- 
rity occurs, it should be at once removed by filtration, 
through charcoal, as it may be safely maintained with Dmitri 
Davidou, probably the best practical writer on the manufac- 
ture of Beet-root sugar, that previous to evaporation, “ the 
juice must be in a state of perfect purity ” To this axiom 
every manufacturer who hopes for success must implicitly 
conform, and the planter in these colonies who chooses to 
incur the extra expense and trouble, will yet find it much 
easier to do so in the earlier stages of manufacture, than 
in manipulating the comparatively weak but complex juice of 
the Beet in Europe, or in refining, an originally low quality 
of Muscovado. 
To attain such purity animal charcoal is the agent almost 
universally employed, but wood charcoal and many shales 
possess similar power and though in less degree have been 
occasionally used as substitutes. To gentlemen connected 
with this Colony it must be interesting and may be profit- 
able to know, that in the Bitumen which exists so abundantly 
in the Pitch Lake and elsewhere, they possess a substance 
