142 TUTTLE ENGINEERING NOTES ON HAWAII. 



400 ft. to 800 ft. below sea level. Coal is obtained from the Canadian 

 and Australian markets, costing about $7 per ton at this plantation, 

 those more remote being obliged to pay higher prices and up to over 

 $10 per ton. 



The mill building has a steel frame covered with corrugated iron, and 

 the floor is of concrete finished with cement. The mill has a capacity 

 of 300 tons of sugar per day, and the equipment consists of settling 

 tanks to hold 24 000 galls., evaporators of 600 000 galls., vacuum pans 

 of 85-ton capacity, forty-five 30-in. to 40-in. centrifugals, and wooden 

 tanks to store 400 000 galls, of molasses. 



The operation of sugar boiling is under the direction of a chemist, 

 who also makes analyses of the soils for the purpose of determining 

 the fertilizer requirement. 



On plantations where an upland water supply is available, the cane 

 is sent to the mill through flumes built of a V- sect io n > and laid on 

 grades of upwards of 1.5 per cent. A flow of about 1.5 cu. ft. per 

 second is required for this purpose. 



Gravity cables are also used to some extent for cane transportation. 



The Sugar Planters' Association maintains a station in Honolulu, 

 where experiments are conducted to determine the relative merits of 

 the various kinds of cane, duty of water, effect of saline water on cane 

 growth, methods of planting, and other matters of kindred nature; 

 here, also, fertilizers are analyzed to determine their conformity with 

 contract specifications. 



For sugar-mill purposes bagasse is almost exclusively used for fuel, 

 and the supply seems to be just about sufficient for this use. The 

 high price of coal and the large quantities consumed for operating 

 pumping plants led to an investigation, in 1901, by Hon. Lorrin A. 

 Thurston, of the possible use of oil for this purpose, attention having 

 been attracted to the fact that coal was rapidly being supplanted in 

 the west by this fuel. From the information thus gathered it was esti- 

 mated that 4 bbls. (168 galls.) of 14 fuel oil was equivalent to 1 

 long ton of Australian coal, and that the former would cost $6 deliv- 

 ered, as contrasted with $10 for the latter. Following this report, 

 negotiations were begun leading to the adoption of this fuel, and 

 contracts for some of the plantations have been placed and the storage 

 tanks are being erected. 



The following statistics concerning the production of sugar were, 



