SALICYLIC ACID AND SALIC YLATES. 589 



GENERAL DISCUSSION OF INDIVIDUAL DATA. 



Some of the noticeable variations in the individual data in regard to 

 the excretion of nitrogen are of interest, Nos. 3, 9, and 10 being ex- 

 cluded as usual. The lowest percentage excreted in the feces in the 

 fore period is found in the case of No. 1, namely, 4.66 per cent, and 

 the highest in the case of No. 6, namely, 10.96 per cent. In regard 

 to the quantity excreted in the urine the largest percentage is found 

 in the case of No. 2, namely, 95.76 per cent, and the lowest in the case 

 of No. 6, namely, 82.30 per cent. No. 2 was decidedly abnormal dur- 

 ing the fore period, since the quantity of nitrogen excreted was greater 

 than that ingested in the food. 



During the preservative period the following notable variations in 

 individuals from the average may be cited: The smallest percentage 

 of nitrogen excreted in the feces is again found in the case of No. 1, 

 namely, 4.22 percent, and the largest, 10.73 per cent, again occurs in 

 the case of No. 6. In the after period the smallest percentage ex- 

 creted in the feces is again in the case of No. 1, namely, 6.31, and the 

 largest, 11.53, No. 8. No. 6, however, maintained a high average, 

 10.43. These data show a consistent idiosyncrasy in the individuals 

 which is practically indicated during all three of the periods. It is 

 evident that No. 1 was able to utilize the nitrogen in the food more 

 completely than were Nos. 6 and 8. 



In regard to the percentage of nitrogen excreted in the urine, the 

 largest quantity in the preservative period is excreted by No 1 3 

 namely, 96.06 per cent, and the smallest quantity by No. 7, namely, 

 80.19 per cent. Of the total number three show an excretion of nitro- 

 gen during the preservative period in excess of the quantity exhibited 

 in the food, namely, Nos. 1, 2, and 6. 



During the after period the largest quantity of nitrogen in the urine 

 is again excreted by No. 1, namely, 96.16 per cent, and the smallest 

 by No. 11, namely, 76.64 per cent. This is, a remarkably low number, 

 but no source of error can be detected from a study of the detailed 

 data and of the character of the man. In the after period only two 

 of the men showed an excess of nitrogen excreted over that given in 

 the food, namely, Nos. 1 and 2. 



It is evident that in the case of a loss of weight a negative nitrogen 

 balance would not be regarded as abnormal. Likewise, in the case of 

 a gain in weight by growth or otherwise, a large positive nitrogen 

 balance would not be regarded as abnormal. Where, however, the 

 weight remains practically constant, any very large positive balances 

 or negative balances require most careful study in order to determine 

 exactly the sources which have caused the variation. The most plaus- 

 ible explanation of an abnormally large positive balance, the energy 

 and food consumed remaining constant, is an increase in the anabolic 



