324 WILEY— INFLUENCE OF PRESERVATIVES [April 25 



total excretion of phosphoric acid under the influence of the copper 

 sulphate. 



The final conclusion, based on the medical and clinical data and 

 on the study of the effect of the copper sulphate upon metabolism, 

 is that the administration of this salt is prejudicial to health. 



Potassium Nitrate. — It is evident that the administration of 

 small quantities of potassium nitrate induce only slight disturbances 

 in the metabolic processes, and indicate only to a slight degree harm- 

 ful or deleterious effects as noted in the medical and clinical data. 

 It is evident moreover that with the exception of one instance, 

 namely, the increase of the number of red corpuscles in the blood, 

 that no beneficial effect can possibly be attributed to the exhibition 

 of this chemical. 



While the data are in this case far less conclusive than those in 

 any of the preceding cases, they are of a character to warrant the 

 suggestion that so far as health and digestion are concerned it is 

 safer to omit a body of this kind from the food. There are some 

 foods which naturally contain small quantities of potassium nitrate. 

 Its very poisonous action when taken in large doses, however, is a 

 warning which should cause great care in its use even in small 

 quantities and deter any one charged with the protection of the 

 public health from expressing any favorable opinion in respect to 

 its use. 



It is evident that potassium nitrate in the quantities used has 

 neither a preserving effect nor has it any condimental value. What- 

 ever may be said to the contrary, it is perfectly evident that the sole 

 purpose of its use is the intensification of the red color of meats 

 after preservation. Whatever may be the ethical principle under- 

 lying this use of potassium nitrate is a question which is not the 

 subject of discussion in a bulletin of this kind, but it is only due 

 to the consumer that the real purpose of using potassiiim nitrate in 

 the curing of meats should be revealed. 



The further question arises as to whether or not the coloring of 

 preserved meats in this way in order that they may have the 

 color of fresh meats is a violation of the Food and Drugs Act, 

 which forbids the coloring of food products for the purpose of con- 

 cealing damage or inferiority. 



