BORIC ACID AND BORAX. 213 



balance becomes a positive number. In the cases of the other mem- 

 bers of the table, during- the fore period the nitrogen balance is posi- 

 tive. During the first preservative subperiod it is negative in the case 

 of No. 4. In the third subperiod the balance is positive in each case 

 except No. 6, while in the after period the balance is positive in all 

 cases. 



The summary of the entire preservative period, namely, December 

 22 to January 3, shows a positive balance in all cases excepting No. 6. 



Comparing now the daily average of the whole class for the differ- 

 ent periods, we find that during the fore period the daily nitrogen 

 balance is 2.12 grams, for the first preservative subperiod 0.83, for the 

 second subperiod 2.24, for the third subperiod 1.20, for the first, 

 second, and third subperiods together 1.40, and for the after period 

 1.73. These data show a tendency in this series toward an increase in 

 the amount of nitrogen excreted during the administration of the 

 preservative. 



SERIES II. 



During this series, on account of illness, the data are not complete 

 for four members of the table, namely, Nos. 8, 9, 11, and 12. In the 

 case of the two remaining members there were periods of temporary 

 illness (grippe), which caused the loss of the data for certain days. As 

 a whole, therefore, this period of observation may be considered as 

 quite unsatisfactory. 



In the fore period, extending from January 19 to 27, inclusive, in 

 the case of No. 7 the average daily nitrogen balance was 0.11 gram, 

 in the case of No. 10 it was 3.66, and for No. 12 it was 5.39. No. 12 

 did not finish the period with the preservative and is therefore 

 excluded from the average. The mean daily average of Nos. 7 and 

 10 is 1.89. 



In the period from January 28 to 31, inclusive, during which 1 gram 

 of boric acid was administered daily, the average daily nitrogen balance 

 increases in the case of No. 7 and remains the same in the case of No. 

 10, while the mean daily balance for the two is 1.63. 



In the second preservative subperiod, extending from February 1 to 

 February 4, inclusive, in which 2 grams of boric acid were adminis- 

 tered daily, the nitrogen balance of No. 7 increases as compared with 

 the fore period, that of No. 10 decreases, and the mean daily balance 

 is 2.52. 



In the third subperiod,*from February 5 to 8, inclusive, in which 3 

 grams of boric acid were administered daily, the balance, as compared 

 with the fore period, increases in the case of No. 7 and diminishes in 

 No. 10. The average daily balance is 1.85. The digestion in all cases 

 after this period became so deranged that the fragmentary data col- 

 lected thereafter are of no comparative value. 



