115 



place, covering periods of about twelve hours' run each, on two fields 

 of cane of very different composition. The figures resulting from these 

 tests, while necessarily not of a high degree of accuracy, are yet as 

 reliable as it was possible to make them with the limited facilities 

 at hand. As only one pair of scales (with a maximum capacity of 500 

 Spanish pounds) was available for weighing cane and bagasse, it was 

 found necessar}^ to weigh the cane during the course of one day, store 

 it under shelter over night and grind the next day, thus leaving the 

 scales available for weighing bagasse. 



The weight of cane actually ground was calculated by subtracting the loss in 

 water by evaporation as determined from a small sample of 1,000 pounds stored 

 under the same conditions. The bagasse was weighed as it came from the mill, 

 in lots of 200 pounds, a sample of 200 grams being taken from each lot and 

 placed in a box over the boiler to dry for analysis. At the end of the run this 

 was chopped into fine pieces, reweighed, quartered, and analyzed, and results cal- 

 culated back to the fresh bagasse and the original cane. The weight of juice 

 was estimated by difference between that of cane and bagasse. 



Although the customary methods of boiling in this locality were 

 followed with as little deviation as possible, some allowance must be 

 made for the mental strain on the native workmen, who were somewhat 

 at a loss to understand the meaning of such an innovation in their 

 ordinary routine; also for the fact that to avoid fracturing the "cauas" 

 it was necessary to follow up the last boiling of juice with pure water, 

 thus incurring a slight loss of a liter or so of juice left behind in each 

 kettle, which in the usual practice would not have occurred. Further- 

 more, it may be stated that these tests, although fairly representative 

 of the working of the average sugar house in Negros, are no longer so 

 of the hacienda on which they were made, as an entirely new plant 

 has been installed there within the past six months. 



MILL CONTEOL NO. 1, HACIENDA SAN JOSE, SAN CARLOS (MAY 1, 1909), 



Equipment. — The mill used was of 12 nominal horsepower, rollers 56 by 106 

 centimeters, power supplied by a multitubular boiler set between the batteries 

 and the chimney, but provided with an independent firing door; steam pressure 

 about 60 potmds to the square inch (4.2 atmospheres). The mill juice runs 

 though an open trough to a series of batteries arranged according to the usual 

 manner, two parallel sets of four in series with the "No. 5" in common. During 

 the experiments one side only was used. No filter presses of any kind were 

 employed, the skimmings from the cauas being thrown into an iron scum tank, 

 which, when full, was allowed to settle as much as possible, the clear juice run 

 back into the battery, and the residue discarded. 



Process of manufacture. — With the exception of the liming of the juice, which, 

 for the sake of uniformity, was all made barely alkaline to litmus in the No. 5 

 "caua," the details of manufacture were left entirely to the native sugar boilers, 

 with instructions to go ahead precisely as was their usual custom. 



