Methods of Bacteriological Examination of Milk.

The bacteriological examination of milk is rapidly becoming one of the essentials in the maintenance of public health. For years milk supplies have been inspected and tested to chemical standards alone, with the result that watered, adulterated, and preserved milks have been practically driven from the markets. These chemical tests are necessary, and only fail in that they do not go far enough, since a milk impure and unwholesome on account of bacterial growth, or a milk from a diseased animal, cannot be detected by them. The bacterial count and the microscopical examination of the milk sediment reveal whether the milk has been properly handled or not, and, to a great extent, the condition of the animal from which it came.