

BORIC ACID AND BORAX. 161 



ued to be excreted. There is a good deal of irregularity in the case 

 of the individual members of the class, which will be indicated suf- 

 ficiently by reference to the tabular statements. It is worthy of note, 

 however, that during the whole of this series no sample of the urine 

 showed an alkaline reaction. 



SERIES IV. 



In Series IV boric acid was replaced by borax, and it is interesting 

 to study the effect which this change had upon the reaction of the 

 urine. 



In the case of No. 8, 5.5 per cent of the samples during the pre- 

 servative period were found to be alkaline. In the case of No. 9 the 

 alkalinity did not appear until the after period, during which 12.5 per 

 cent of the samples showed an alkaline reaction. The same is true of 

 No. 10. In the case of No. 11 there was no alkaline reaction, but the 

 number of samples that were acid fell from 50 per cent in the fore 

 period to 9.1 per cent in the preservative period, while those marked 

 as amphoteric rose from 25 per cent in the fore period to 90.9 per 

 cent in the after period. Thus the tendency to diminished acidity was 

 very strongly marked in the case of No. 11, although no actual alka- 

 line reactions were noticed. In the case of No. 12 a remarkable change 

 in the same direction was also manifested. The number of samples 

 that were acid in the fore period was 50 per cent, while in the pre- 

 servative period there was none, whereas the number marked ampho- 

 teric rose from 37.5 per cent to 88.8 per cent, and 11.1 per cent of the 

 samples in the preservative period gave an alkaline reaction. In the 

 case of No. 7, who withdrew at the end of the preservative period, we 

 see also a marked tendency to diminish the strongly acid reaction, 

 although in no case was there an alkaline reaction. 



The best comparisons in this instance are made between Nos. 8, 9, 

 and 10, who completed in an even manner the whole of the series. In 

 this comparison it is seen that during the fore period the per cent of 

 samples strongly acid was 25, during the preservative period 7.4, and 

 none during the after period. The effect of the borax, therefore, in 

 diminishing strong acidity was very marked and extended through the 

 after period. The samples acid in the fore period included 51.1 per 

 cent, in the preservative period 64.8, and in the after period 37.5. 

 Those that gave an amphoteric reaction in the fore period included 

 20.8 per cent of the samples, during the preservative period 25.9 per 

 cent, and during the after period 54.2 per cent. During the fore 

 period there were no samples giving an alkaline reaction, during the 

 preservative period 1.8 per cent gave an alkaline reaction, and during 

 the after period 8.3 per cent. 



These data show the very marked effects of the borax toward 

 diminishing acidity and would indicate that all, or at least a large 

 4242 No. 84, pt 104 11 



