Pasteurized milk, according to the definition of the Secretary of Agriculture, is milk that has been heated below the boiling point, but sufficiently to kill most of the active organisms present, and immediately cooled to 50 F. or lower. The process of pasteurization as we know it to-day is employed either to prevent communication of disease through milk to the consumer or to avoid "disease of milk." The process was first worked out by Pasteur to preserve wine and beer and had no reference to diseases of man. Soxhlet in 1886 devised tubes and methods for sterilizing milk so that it would keep. These methods were introduced into the United States by Caillé1 in 1888, who, in an article on the subject, states that some thirteen years before Jacobi had recommended sterilization of milk. These methods all had as their object the preservation of milk and it was not