FIFTEENTH ANNUAL REPORT 31 



classes of work and their places filled by those having the re- 

 quired ability. With the object of encouraging briquette mold- 

 ers to put forth their best efforts, a bonus system has been 

 devised. Although received irregularly, the number of cements 

 tested has been greater than during any former year. Not only 

 has there been a large number of requests at one time for 

 cement tests, but also requests asking that certain samples be 

 rushed. In order to complete all of the w^ork without delay, 

 the laboratory has been arranged so that at any time the output 

 can be temporarily doubled by detailing some of the regular 

 shifts to night dutj^ and filling the gaps with new recruits. 



INVESTIGATION 



In this division, as in the other branches of the Bureau of 

 Science, a scientific study of Philippine problems is indispensable 

 and men can be of the greatest value only when they devote 

 considerable time to careful study. This study is guided along 

 the lines of Philippine industry. 



The present European war has brought about a shortage of, 

 and an increase in, the price of sodium peroxide, the chief chem- 

 ical used for bleaching native hats. In order to remedy this 

 shortage and to make bleaching agents available, the Bureau of 

 Science has carried on a number of experiments with a view 

 to find other chemicals obtainable in the local market at a 

 reasonable price that would serve equally well. The results of 

 these experiments show that sodium hypochlorite is adapted for 

 bleaching native hats and can very well replace sodium peroxide. 

 It is now being used by some hat factories for this purpose. 

 Sodium hypochlorite can be readily prepared from bleaching 

 powder and sodium carbonate or by direct electrolysis of a solu- 

 tion of common salt. The preparation of sodium hypochlorite 

 from bleaching powder and sodium carbonate has been found 

 economically possible on account of the fact that these chemicals 

 are available in the local market and can be readily secured from 

 Japan or from the United States at reasonable prices. The 

 preparation of sodium hypochlorite by direct electrolysis of salt 

 brine requires an initial outlay, but in the long run is more 

 economical than the other process. With either of these two 

 processes a cheaper bleaching agent than sodium peroxide can be 

 produced. 



After several years of planning, we were able to keep a man 

 for over six months of the year at field work in water analysis. 



