Over a period of a week, the tactics had gone from infantile to novice to advanced, as if someone were learning the intricacies of battle planning.
On the other hand, not a few disorders proved to be alien to classes to which narrower views of causation had referred them; of such are tabes dorsalis, neuritis, infantile palsy or tetanus, now removed from the category of primary nervous diseases and placed in one or other of the class of infections; or, conversely, certain forms of disease of the joints are now regarded with some certainty as members of more than one series of diseases chiefly manifest in the nervous system.
The ghastly roll of infantile mortality was quickly purged of its darkest features (Ballard and others); aided by bacteriology, sanitary measures attained some considerable degree of exactness; public medicine gained such an ascendancy that special training and diplomas were offered at universities; and in 1875 a consolidated act was passed for the United Kingdom establishing medical officers of health, and responsible lay sanitary authorities, with no inconsiderable powers of enforcing the means of public health in rural, urban, port and other jurisdictions, with summary methods of procedure.
In infantile palsy, for example, and in tabes dorsalis, there is good reason to believe of that, definitely as the traces of the disease are found in certain physiologically distinct nervous elements, they are due nevertheless to toxic agents arriving by way of the blood.
That infantile paralysis is an infection, and that its unhappy sequels are now treated with more hope of restoration, has been indicated already.