712 INFLUENCE OF FOOD PRESERVATIVES ON HEALTH. 



sample of the fore period in the case of No. 3 is 91.1, in the composite 

 sample of the preservative period 90.4, and in the average of daity 

 samples of the after period 91, indicating a slight tendency on the part 

 of the preservative to decrease the relative amount of nitrogen excreted 

 as urea. 



In regard to the percentage of nitrogen excreted as uric acid in the 

 case of No. 3 in the fore period, it is 1.5, in the preservative period 

 1.2, and in the after period 1.4 per cent, in each case determined in 

 the composite sample. These data indicate a tendency on the part of 

 the preservative to diminish the relative proportion of uric acid nitro- 

 gen eliminated. 



SUMMABY. 



We now have to consider the case of Nos. 1, 2, and 3 as a whole. 

 It is seen that the average daily volume of urine excreted in the fore 

 period is 893 cc, in the preservative period 981 cc, and in the after 

 period 1,298 cc. These data indicate that the general effect of the 

 preservative is to act as a diuretic, and this effect is enormously in- 

 creased immediately after the withdrawal of the drug. This would 

 seem to indicate that the maximum excitation produced by the exhibi- 

 tion of salicylic acid is not manifested immediately at the time of its 

 administration, nor within six days, but is shown in a much more 

 marked degree immediately after the administration is withdrawn. 

 In other words, the stimulation of the excretory organs eliminating 

 urine does not reach its maximum until some time, at least six days, 

 after the first administration of the preservative. 



The average quantity of nitrogen ingested daily is 16.10 grams. Of 

 this, there is eliminated in the fore period in the urine 13.689 grams, 

 in the preservative period 13.429 grams, and in the after period 14.009 

 grams. These data show a slight general tendency on the part of the 

 preservative to diminish the quantity of nitrogen eliminated in the 

 urine during the administration of the preservative, but the elimina- 

 tion is increased in the after period. 



In regard to the nitrogen eliminated as urea, as determined by the 

 first method, it is seen that in the fore period the average daily amount 

 is 12.348 grams, for the preservative period 12.180 grams, in the com- 

 posite samples, respectively, and for the after period 12.638 grams in 

 the average of daily samples. The general indication, therefore, is 

 that the effect of the preservative is to slightly diminish the total 

 quantity of nitrogen eliminated as urea, but the quantity eliminated is 

 increased to above normal on the withdrawal of the preservative. 



The average daily quantity of uric-acid nitrogen excreted in the com- 

 posite sample of the fore period is 0.201 gram; in the composite sam- 

 ple of the preservative period 0.177 gram, and in the composite 



