PRESERVATION BY THE USE OF CHEMICALS. 243 
helping to preserve fruits and vegetables that would otherwise soon 
spoil. The value of ice as an aid in keeping all sorts of perishable 
material is too fully understood to require further notice. 
PRESERVATION BY THE USE OF CHEMICALS. 
Many chemical substances are destructive to bacteria, and foods 
may frequently be protected from bacterial action by the addition of 
small quantities of some material, harmless in itself, yet having 
a checking action upon bacteria. Such agents are called preserva- 
tives. If they are to be used in the preservation of food products, it 
is of course necessary that they should not be deleterious to health 
and also that they should not impart disagreeable flavors to the food. 
The number of substances that can be used without hesitation is not 
very great. 
The more powerful antiseptics, like carbolic acid and corrosive 
sublimate, are, of course, out of the question. Certain milder ones, 
borax, boracic acid, salicylic acid, formalin and benzole acid, are more 
or less extensively used. There are on the market various com- 
mercial preservatives, Preserualine, Anti-fermentine, Freezine, etc. 
These several articles have different compositions, but all are wholly 
or in part made up of the substances named, most of them being 
either borax or formalin. They are undoubtedly efficient in pre- 
venting putrefaction and decay, for they are antiseptics, and if used 
in sufficient quantity will stop bacteria growth. They have been 
widely used in meats and in milk. 
But the question arises whether they are not injurious to health. 
Each is injurious to man if taken in sufficient quantity. Are they, 
then, objectionable in the small quantities used in preserving food ? 
This question has led to much experimenting, especially by the 
U. S. Department of Agriculture. The general result of these exten- 
sive experiments is to show that these preservatives, when used in 
small amounts day after day, are injurious, although this conclusion 
is still disputed. Hence, the general conclusion is that the pre- 
servatives in question are to be condemned. They are certainly 
illegitimate, and, since the same results can be reached in another 
