of forgetfulness of the poor,” as the Council of Hygiene mildly put it, has of avenging itself.

The determined effort to head it off by laying a strong hand upon the tenement builders that has been the chief business of the Health Board of recent years, dates from this period. The era of the air-shaft has not solved the problem of housing the poor, but it has made good use of limited opportunities. Over the new houses sanitary law exercises full control. But the old remain. They cannot be summarily torn down, though in extreme cases the authorities can order them cleared. The outrageous overcrowding, too, remains. It is characteristic of the tenements. Poverty, their badge and typical condition, invites—compels it. All efforts to abate it result only in temporary relief. As long as they exist it will exist with them. And the tenements will exist in New York forever.