244 INFLUENCE OF FOOD PRESERVATIVES ON HEALTH. 



ance is 544.701 grams. During the preservative periods the average 

 daily quantity of solids in the food is 627.6, of which 28.6 grams 

 appear in the feces and 88.025 grams in the feces and urine; 4.6 per 

 cent of the total solids in the food appear in the feces and 14 per cent 

 in the feces and urine. The average daily balance is 539.875 grams. 

 In the summary of the after periods it is seen that the average daily 

 quantity of solids in the food is 614.1 grams, of which 28.3 grams 

 appear in the feces and 84.677 in the feces and urine; 4.6 per cent of 

 the total solids in the foods appear in the feces and 13.8 per cent in 

 the feces and urine. The average daily balance is 530.123 grams. 



This general summary confirms the conclusion based upon the indi- 

 vidual series. It shows a slight tendency on the part of the preserv- 

 ative to increase the percentage of solids in the food eliminated in the 

 feces, and this increase continues in the same magnitude during the 

 after period. This continued effect is easily explained by the tendency 

 established in the long exhibition of the preservative to slightty derange 

 the digestive functions. It requires at least half of the after period 

 to secure the elimination of the preservative from the digestive sys- 

 tem, and the other half of the after period is evidently too short a 

 time to secure in every case the reestablishment of normal conditions. 



SUMMARY OF RESULTS. 

 EXCRETION OF ADDED PRESERVATIVES. 



The boric acid and borax taken into the stomach during the progress 

 of these experiments were excreted almost entirely by the kidneys. 

 (See Tables III- VIII.) In the first series of experiments 83.05 per 

 cent was thus excreted, in the second series 82.85 per cent, in the 

 third series 63.87 per cent, in the fourth series 82.96 per cent, and in 

 the fifth series 75.17 per cent. During the course of observation 

 607.4 grams of preservative were given, either in the form of boric 

 acid or the equivalent in borax, of which 468.69 grams were excreted 

 in the urine, or 77.16 per cent of the whole. (See Table VIII.) 

 These numbers include the data for Series III, where the quantity of 

 the preservative recovered in the urine appears to be abnormally low. 

 In round numbers it may be said that 80 per cent of the boric acid 

 and borax taken into the system in foods is excreted in the urine. It 

 is probable that the rest is chiefly excreted with the perspiration. 

 Only small quantities are found in the feces. 



INFLUENCE OF THE PRESERVATIVE UPON THE WEIGHT OF THE BODY. 



In every series there was a marked tendency on the part of boric 

 acid and borax to diminish slightly the weight of the body, although 

 this tendency was in some instances checked during the after periods 



