The work went on; but the need of it only grew with the effort. The Sanitarians were following up an evil that grew faster than they went; like a fire, it could only be headed off, not chased, with success. Official reports, read in the churches in 1879, characterized the younger criminals as victims of low social conditions of life and unhealthy, overcrowded lodgings, brought up in "an atmosphere of actual darkness, moral and physical." This after the saw had been busy in the dark corners ten years! "If we could see the air breathed by these poor creatures in their tenements," said a well-known physician, "it would show itself to be fouler than the mud of the gutters." Little improvement was apparent despite all that had been done. "The new tenements, that have been recently built, have been usually as badly planned as the old, with dark and unhealthy rooms, often over wet cellars, where extreme overcrowding is permitted," was the verdict of one authority. These are the houses that to-day perpetuate the worst traditions of the past, and they are counted by thousands. The Five Points had been cleansed, as far as the immediate neighborhood was concerned, but the Mulberry Street Bend was fast outdoing it in foulness not a stone's throw away, and new centres of corruption were continually springing up and getting the upper hand whenever vigilance was relaxed for ever so short a time. It is one of the curses of the tenement-house system that the worst houses exercise a levelling influence upon all the rest, just as one bad boy in a schoolroom will spoil the whole class. It is one of the ways the evil that was "the result 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. [Illustration: TENEMENT OF THE OLD STYLE.] [Illustration: BIRTH OF THE AIR-SHAFT.]