238 INFLUENCE OF FOOD PRESERVATIVES ON HEALTH. 



very suggestive. Whether this influence is due to an actual inhibitory 

 effect of the borax upon the combustion of the food, or whether it is 

 due to a diminution in the activity of the first processes of digestion, 

 whereby less of the combustible material is made available for absorp- 

 tion and assimilation, can be determined only 03^ a more intimate com- 

 parative study of the composition of the feces and urine. 



SOLIDS BALANCE. 



The object of this study is to ascertain the total dry matter in the 

 food and its fate in the alimentary canal and in metabolism. The 

 moisture-free matters ingested are compared with the total solids 

 recovered in the feces and urine. This has been done for each indi- 

 vidual member of the class for each series and for the periods and 

 subperiods of the investigation. Tables LXXXV-XCV (pp. 423-461) 

 contain the daily data for each case. 



SEKIES I. 



In Series I the part of the fore period covered is December 16-21 

 only. It will be sufficient for the purposes of the discussion to call 

 attention to the summaries rather than to the individual data. The 

 latter are found in the tables, and if a more detailed stud} 7 of indi- 

 viduals is desired these can be utilized. 



Of 20,603.9 grams of solids ingested in the food in the period men- 

 tioned, 865.5 grams, or 4.2 per cent, are found in the feces and 9.7 per 

 cent in the urine. The total percentage recovered in the feces and 

 urine is 13.9, and the balance is 17,731.432 grams. The average daily 

 quantity of solids in the food of each person is 589 grams, of which 

 24.7 appear in the feces and 82.04 in the feces and urine. The daily 

 balance is 506.958. In the first preservative subperiod, extending 

 from December 22 to December 26, it is seen that 4.4 per cent of the 

 ingested solids appear in the feces and 14.5 in the feces and urine. 

 The average daily quantity of solids in the foods for this period is 

 605 grams, of which 26.4 grams appear in the feces and 87.59 grams 

 in the feces and urine. The average daily balance during this period 

 is 517.408 grams. During the second subperiod the average daily 

 solids in the food are 635 grams, of which 28.3 grams appear in the 

 feces and 86.221 in the feces and urine, leaving a balance of 548.779 

 grams. The percentage of total solids excreted in the feces during 

 this period is 4.5 and in the urine 9.1. During the third subperiod 

 the average quantity of solids in the food is 569 grams, of which 28.5 

 appear in the feces and 56.97 in the urine. There is an elimination 

 of 5 per cent in the feces and 10 per cent in the urine. The balance 

 is 483.503 grams. In the three preservative subperiods taken together 

 the average daily quantity of dry food ingested is 602.5 grams, of 

 which 27.6 appear in the feces and 86.516 in the feces and urine. The 



