6. A sugar refinery is operated the entire twelve months of the year, while a raw-sugar mill must of necessity take care of the crop of cane in about eight months. To refine sugar where it is grown would require refining machinery capable of handling the entire output in the eight-month period, and during the remaining four months the plant would remain idle. This would mean a larger investment proportionately than that made in a refinery in a consuming center, running steadily the year round. 7. Refined sugar very rapidly absorbs moisture, and while in transit from the tropic to the temperate zone it is very apt to become lumpy or caked, which would involve reprocessing at great expense at the point of consumption. The unavoidable damage to the packages in loading and discharging results in heavy expense, as all packages must be delivered to the buyer in first-class condition. To avoid hardening, refined sugar should never be piled very high, and it is an unsolved problem whether refined sugar will stand long ocean transportation in cargo lots without caking and damage by breaking of the inside cotton sacks. If shipped in barrels, the freight rate is proportionately higher. 8. Larger capital would also be required, as refined sugar must be carried on hand and must await the consumer’s demand, while raw sugar generally has a prompt and ready market and can be quickly converted into cash. With these difficulties presenting themselves to a prospective sugar refiner in a raw-sugar-producing country, the shipping of raw sugar to refineries at great distances does not seem at all unreasonable. Raw sugars show considerable variance in their component parts, and so it follows that some are less easily refined than others. Such differences are generally due to diverse methods of culture, amount of fertilizer used, the processes of manufacture and the efficiency of extraction. If the extraction be high, a large percentage of the salts in the cane is taken up, and these salts prevent or retard the complete crystallization of the pure sugar in refining. One part of ash prevents several times its own weight of sugar from crystallizing, hence it is readily seen that raw sugars with a low ash content are preferred by refiners. [Illustration: A MODERN REFINERY—SHOWING WATER AND RAIL TRANSPORTATION FACILITIES] [Illustration: PLAN ELEVATION OF A MODERN REFINERY] Sugar refining is the production of pure white sugar in granular form, after the removal of the impurities from the raw product. Nine operations are necessary to bring about this result: 1. _Washing_: Removal of superfluous impurities. 2. _Melting_: Changing the solid raw sugar into liquid form by melting with water. 3. _Defecation_: Precipitation of suspended and insoluble impurities. 4. _Bag and Bone-char Filtration_: Removal of suspended impurities, color and soluble impurities. 5. _Crystallization_: Production of crystals by concentration.