,9o8.] ' UPON HEALTH AND METABOLISM. 325 



While, therefore, the data which have been accumulated are not 

 such as to warrant a sweeping condemnation of potassium nitrate in 

 foods, they are sufficiently indicative to justify the conclusion that 

 its presence in foods is undesirable and open to suspicion. 



General Considerations. 

 Having thus set forth the general results of this long and labor- 

 ious study, it is seen that if the conclusions based upon the experi- 

 mental data are correct that there can be no justification of the proc- 

 ess of adding chemical preservatives to human foods. Successful 

 manufacturing establishments have demonstrated beyond peradven- 

 ture that better, more wholesome, and more permanent forms of food 

 products can be produced without the aid of any preservative what- 

 ever. Sterilization will preserve sweet cider better than benzoate of 

 soda. Proper care in handling fruits and in conducting the manu- 

 facturing processes for preserves, jams and marmalades will make 

 a more palatable product and one that keeps better than the use of 

 salicylic acid. Careful curing of meats and proper care in trans- 

 portation will preserve these meats better than boric acid. The 

 natural color of the pea kept in a sanitary can where its color is 

 not lost by action due to imperfections of the tin will make a far 

 more palatable article than will the use of sulphate of copper, and 

 so on to the end of the list. There is no single food product which 

 is not more palatable and of equal if not better keeping qualities 

 when made carefully without the use of preservatives. There is, 

 therefore, absolutely no commercial necessity for the use of these 

 bodies, but it is urged by those who employ them that even though 

 considerable quantities of these bodies are injurious to the health, 

 which no one denies, yet in the minute" quantities in which they are 

 used in foods they can not be regarded as in any way deleterious. 

 It is easy to show that such an opinion is without scientific basis. 

 It is quite impossible for any expert who holds this opinion to indi- 

 cate to any jury, much more to the great jury of the American peo- 

 ple any point in the addition of the preservative to food at which 

 it remains harmless, or the point at which it begins to be harmful. 

 Unless such a point could be fixed and demonstrated upon reliable 



