INTRODUCED PLANTS AND ANIMALS. 275 



refuse and trash being left on the ground to l)e burned hiter on. The trimmed 

 stalks, which average eight or ten feet in length and more than an inch and a 

 half in diameter, are loaded upon carts or cars drawn over portable tracks by 

 horses or by small locomotives. Where there is a surplus of water the cane 

 is often floated to the mill in the flumes. In this way the water flumes are 

 utilized in the production and harvesting of the crop in both wet and dry 

 districts. 



The loaded car on arriving at the unloading shed is brought alongside 

 a moving floor that, in reality, is a wide endless chain-belt that carries the 

 cane to the elevator. The cane in most cases is unloaded by machinery that 

 pulls the load from the car to the moving floor. From the floor the cane is 

 elevated on a conveyor which delivers it to a pair of large corrugated rollers 

 that crush the stalks, extracting much of the .juice. The crushed mass is then 

 passed through several sets of rollers, each set made up of three close-fitting 

 cylinders. In the final crushing process, hot water is added to aid in extract- 

 ing the last particle of .iuice that may remain. The dry mass, now called 

 "bagasse," is carried on elevators to the furnace room, where it is used at once 

 for fuel. 



The juice from the rollers is collected and conducted to the liming tank, 

 where a chemical change is effected by adding slaked lime. From a receiver 

 near the liming tank the juice is passed to the settling tanks. 



After it has stood a few hours, the juice of the top portion is drawn off 

 and the muddy lower portion agitated by steam. This hot mixture is then 

 passed to the mud jiresses, where the clean juice is separated from the mud. 

 The liquid mixed with the clear juice from the settling tank is next conveyed 

 to the evaporating pans, where it is changed by heat from juice into syrup. 



The evaporators are a series of four or more large iron boilers connected 

 one with the other. The air is removed from them in order to create a partial 

 vacuum. The juice will then boil with less heat and the syrup is jn-evented from 

 scorching. The s.vru]i, when sufficiently reduced, is conveyed to the vacuum 

 pans, where the grain in the thick molasses is produced b.v another boiling. 



At this stage inventors have made man.v improvements in the process by 

 which the thick mass is passed into the crystallizers, where the syrup or sucrose is 

 made into firm, dry grains. Small amounts of syrup are transferred to the tub- 

 like machines called centrifugals. These tub-shaped cylinders have central cavi- 

 ties made of wire netting. This wire cage revolves rapidl.v and by centrifugal 

 force throws the molasses out. retaining the crystals of sugar within the cage. 

 The uncrystallized liquid is carried to the boilers again and is made into 

 second-grade sugar. The higher grade sugar drops from the centrifugals into 

 a large retort known as the drying machine. Through this the sugar works 

 its way among hot coils that dry the crystals before they are carried to the 

 sugar bin. From this bin the raw sugar is drawn out, sacked and weighed. 

 Each burlap sack contains about 125 pounds of light-brown sugar. 



]\Iost of the sugar is sent as light brown, or raw% sugar to the mainland of 



