102 



weight, and most of these particles should become soft after an hour's standing 

 in a moist condition. The lime, after being slaked, should dissolve in hydrochloric 

 acid without appreciable effervescence and not leave more than 2 per cent insoluble 

 matter. The maximum percentages of impurities should be: 



Per cent. 



Iron oxide and alumina 2 



Sulphuric acid 0.50 



Magnesia 2 



Silica 2 



Carbonic acid „...,. 2 



Moisture 2 



A sample of the lime used in Negros as tested there was found to contain about 

 50 per cent of hard lumps, which would not soften when mixed with water. On 

 treating it with dilute hydrochloric acid, the greater portion of it dissolved, 

 although very slowly, and with much effervescence. A sample was bottled and 

 sent to the Bureau of Science, Manila, where it was analyzed by Mr. L. A. 

 Salinger : 



Per cent. 



Loss on ignition 36.81 



Iron oxide and aliimina 1.39 



Magnesia 8.35 



Silica 1.42 



Calcium oxide 51.42 



Total 99.39 



Carbonic acid 10.81 



Its high percentage of magnesia alone should cause it to be rejected. Sub- 

 tracting from the total lime that portion present as the carbonate leaves only 

 37.66 per cent of calcium oxide, as such, in the mixture, and a large proportion 

 of this is in such hard lumps as to be unavailable for clarification. From the 

 standpoint of economy, a fairly pure quicklime would be cheaper at three times 

 the price. 



Boiling to a concrete. — When a "cocida" or strike of "massecuite" has been 

 taken out of the "caua mayor," the latter is refilled as quickly as possible (a 

 few minutes' delay might cause the kettle to become overheated and crack) with 

 sirup from No. 2, which by this time has become fairly clear and has been con- 

 centrated to about 50° Brix; fresh bagasse is thrown on the fire, and in a short 

 time the pot begins to boil furiously. As the sirup evaporates it is replenished 

 from No. 2, and any last, remaining, flocculent impurities rising to the surface 

 are swept back into the latter. When the "maestro" decides that sufficient sirup 

 has been taken in to yield a "cocida" of the desired size — from 100 to 300 kilos 

 of sugar are taken out at a time — -he declares No. 1 "caua" closed, and no 

 further additions are made to it, but the whole mass is boiled down as rapidly 

 as possible until a small sample taken with a stick shows it to be of the proper 

 consistency to take out. At this point the fires are drawn and the "massecuite" 

 poured out into wooden trays, termed "enfriaderas," where it is "crystallized in 

 motion" by stirring with a spade. The time required for crystallization depends 

 much upon the kind of sugar produced, and an experienced sugar maker can, 

 from the behavior of the "massecuite" in the "enfriaderas," form a pretty accurate 

 opinion of the quality of sugar which is being turned out. A high-grade "mas- 

 secuite" will begin to boil up almost as soon as it strikes the cooling trays, and 

 will subside quickly, only to rise up again in a minute or so. If this rising and 

 falling is very energetic and occurs two or three times in quick succession, it is 



