And many acquisitions had been made by the Vestries and District Boards, and, since their supersession, by the Borough Councils.

Purity of air was another of the important elements of a satisfactory health condition.

Once that the Thames had ceased to be the main sewer of London, and once that the hundreds of thousands of cesspools were filled in and abolished, the most persistent and fruitful and worst of the causes of the impurity and unwholesomeness of the atmosphere were removed. Gradually too, but only too slowly—a slowness resulting in widespread loss of health and life—were the noxious trades in London made amenable to the law, and somewhat less noxious to those living in their immediate neighbourhood; this, too, without that ruin to trade and manufactures which was always predicted when any effort was made to prevent the prevalence of intolerable nuisances.

The duty of administering the provisions of the law relating to the abatement of smoke nuisances rested with the police. Under their action a steady reduction had taken place in offences against the law. In 1882, 1,248 cases were reported, and there had been 162 convictions; and in 1890 the numbers had sunk to 702 reported cases and 46 convictions.

In 1891, by the Public Health London Act, the duty was transferred to the Sanitary Authorities. Considerable use has been made by them of the Act. In many cases severe penalties were imposed, and the general result has been a very satisfactory improvement. Much, however, of the fouling of the atmosphere is caused by factories outside London, and consequently outside the control of the local authorities of London.

And yet another of the great branches of the general subject of the public health is the food supply of the people. It would be difficult to give any approximate estimate even of the part which good or bad food has in its effect upon the public health, or to produce any statistics on the subject, but, undoubtedly, it is a very large part; and every now and then the outbreak of some serious illness and heavy loss of life, directly traceable to the consumption of bad food, shows how important it is to safeguard the people from such disasters.

Thus in 1901 there was an outbreak of scarlet fever, in which some 300 persons were attacked, directly traced to an infective milk supply.

Previous to the date of the Nuisances Removal Act of 1855 there was, so far as London was concerned, practically no control or supervision over the food sold to and consumed by the people. That Act contained a section providing for the inspection of food by the local sanitary authority, so the importance of securing wholesome food for the people was then recognised. Little, if any, use was made of the power thus given, and the Act was amended and extended; but even then it was almost a dead letter.

As years advanced great scientific discoveries demonstrated the fact that some of the most dangerous diseases, such as typhoid and scarlet fever, could be conveyed in food of various sorts, and opened up a new vista of dangers as to the conveyance of disease.[194] And the huge size of London, and the vast numbers of its population, increased enormously the difficulty of safeguarding the public from the dangers of contaminated food.