Dr. Peabody defines sanitary science as not only dealing with waste disposal, food and drug quality, and the state of living arrangements, but also encompassing "hygiene, physiology, heredity, & preventive medicine." Sanitary science is in its "infancy," but much has already been accomplished with the help of sanitary knowledge. Statistics of declining death rates in London and the conquering of scurvy on ships prove this point. He chronicles the history of the growing field of sanitary science through important speeches, literary publications, and the founding of public health associations.
He then describes the structure and functioning of England's governmental public health system. Peabody claims that medicine and sanitation are wedded, not entirely separate, entities as many believe.