The three diseases which were especially regarded as due to filth were cholera, typhus, and enteric fever; and the history of public health in England is largely concerned with these three diseases. _Cholera_ The general view then held in New as in Old England is well stated in the following extract from the Report of the Massachusetts Sanitary Commission, 1850: Atmospheric contagion is generally harmless unless attracted by local causes ... that terrible disease, Asiatic Cholera, derives its terrific power chiefly or entirely from the accessory or accompanying circumstances which attend it. It bounds over habitation after habitation where cleanliness abides; ... while it alights near some congenial abode of filth or impurity.... Wherever there is a dirty street, court, or dwelling-house, the elements of pestilence are at work in that neighbourhood. And the important moral is drawn that the person who permits his neighbour’s atmosphere to be contaminated by any filth ... is worse than a highway robber. The latter robs us of property, the former of life. Similarly, Simon in England was teaching that “in order to the prevention of Filth Diseases, the prevention of filth is indispensable”; and that there was need for local authorities “to introduce for the first time, as into savage life, the rudiments of sanitary civilization.” The crude generalization that filth causes disease perhaps persisted too long, and the value of Snow’s investigation in 1855 of the outbreak of Cholera in the area of supply of the Broad Street pump was perhaps too slowly appreciated. The influence of Von Pettenkofer’s theories on the relation between subsoil conditions and Cholera was largely responsible for this delay; but already in 1856 Simon had accepted the importance of water infection, giving as his general conclusion that under the specific influence which determines an epidemic period, fecalised drinking water and fecalised air equally may breed and convey the poison (of Cholera). Still it will be noted there persisted the notion of aerial convection of the contagia of cholera and enteric fever, in addition to their convection by dirt, by flies, or the more common contamination of hands or feet or food by faecal matter; but the importance of water supplies was beginning to be appreciated. Already in 1883 local authorities in England and Wales had outstanding loans for waterworks amounting to twenty-nine million and for sewerage amounting to fifteen million pounds sterling, while between 1883 and 1912 they expended out of rates and by means of loans one hundred and thirty-one millions for waterworks and eighty-nine millions sterling for sewerage. Although we realise now the greater importance of control of excreta from persons specifically infected, we must agree with Simon that communally