641 
Milk presents the strange contradiction of being the most whole- 
some single foodstuff, and sometimes one of the most poisonous of all 
foods. A single feeding of a few gills of milk containing pathogenic 
bacteria or the toxic products of bacterial activity frequently results 
in sickness and death. Milk sometimes contains such violent poisons 
as to cause death in a few hours. Ordinarily, milk contains very 
many bacteria ; in fact, milk containing less than 10,000 bacteria per 
cubic centimeter is considered of excellent quality, and milk con- 
taining 100,000 bacteria per cubic centimeter is generally considered 
good. 
Of all foodstuffs, milk is the most difficult to preserve pure and 
handle with success. It requires not only intelligence, but a high 
degree of technical training, as well as incessant vigilance, to produce 
a clean and safe milk. Many believe that this end may be accom- 
plished by official supervision and a good system of inspection. 
However, we can scarcely conceive of any system of surveillance of 
the milk supply that will prevent its occasional contamination. In 
fact, the highest grade of certified milk has at times been accused of 
causing outbreaks of disease. Such lapses are infrequent and the 
danger slight. These facts are stated not as an argument that certi- 
fied milk should be pasteurized, but simply to show the difficulties of 
obtaining a safe raw product. 
Preventive measures are better than corrective ones. Pasteuriza- 
tion can not atone for filth. Milk should be produced under clean 
conditions and kept clean and it would not then have to be purified. 
But we must guard against enemies as long as they exist. We would 
all like to do away with the necessity for armies and navies, but pres- 
ent conditions demand their maintenance. The same is true of harm- 
ful bacteria in milk; so long as the average market milk is apt to 
contain these insidious foes, the only protection we have is to destroy 
them with heat. 
There can be no more objection to the heating of milk for the use 
of adults and of children above the age of 3 years than there is to the 
cooking of meat. Even Fliigge,® who was one of the first to sound 
the warning that heated milk may subsequently develop poisonous 
properties for infants, has no objection to the heating of milk for the 
use of adults and of children above the age of 3 years. 
The question naturally arises, Is the danger from the use of the 
average raw market milk a serious one? Our investigations * * 6 in 
Washington have shown that the general market milk is, for the 
° Fliigge : Die Aufgaben nnd Leistungen der Milchsterilisirung gegeniiber den 
Darmkrankheiten der Sauglinge. Zeit. f. Hyg., vol. 17, 1894, p. 272. 
6 Rosenau, Lumsden, and Kastle, Bulls. 35 and 44, Hyg. Lab., U. S. Pub. 
Health and Mar. Hosp. Serv., Wash., 361 pp. 
1414— Bull. 56—09 41 
