ILLINOIS STATE DAIRYMEN'S ASSOCIATION. 107 



it was claimed by the manufacturers that a teaspoonful of it 

 when added to a pint of milk '' will neutralize all disease germs, 

 bacteria, microbes, bacilli, and other impurities." The inves- 

 tigator found that it was a solution containing nineteen per cent, 

 of potassium nitrate, or saltpetre, dissolved in water. Instead of 

 being a neutralizer of germs, etc., there were many kinds of 

 germs, bacteria, swarming in it, and on the whole a substance 

 which would contaminate the milk and not preserve it. 



The chromates of potassium are used as milk preservatives. 

 Two of these compounds are potassium chromate and potassium 

 dichromate. The difference between the two compounds may 

 be briefly stated is that the first contains twice as much 

 potassium as the second. The potassium chromate has been 

 used for the preservation of milk by some dealers of some cities 

 of Europe who use certain yellow powders consisting of potassmm 

 chromate and potassium dichromate. The milk on examination 

 was found to contain these powders to the extent of five grams 

 per quart. Such action on part of the milk dealer would 

 indicate very great ignorance or little interest in the welfare of 

 his customers. Corrosive sublimate is more generally used I 

 believe than any of the preservatives for composite samples. 

 One of the greatest objections against it is that it is a powerful 

 poison and many realize this danger. It is, however, one of the 

 best preservatives for composite samples that we have. When 

 manufactured in the form of tablets it is a very convenient 

 preservative in the creamery. 



In conclusion I would call attention to the use of preservatives 

 in food, and especially dairy products, which there is a tendency 

 on the part of some to use. It is wrong I think to make use of 

 any preservative in any article intended for food. The customer 

 has a right to receive the food purchased by him in a pure con- 

 dition. 



As to the choice of a preservative for composite samples 

 there are three of about equal value for this purpose: corrosive 

 sublimate, formaldehyde, and potassium dichromate, and I 

 would recommend that you select either of these best suited for 

 your purpose and purchase it according to its name, and not 



