Eighty per cent. at least of the crimes against property and against the person are perpetrated by individuals who have either lost connection with home life or never had any, or whose homes have ceased to be sufficiently separate, decent, and desirable to afford what are regarded as ordinary wholesome influences of home and family. The younger criminals seem to come almost exclusively from the worst tenement-house districts. These tenements, it seems, are slums. Of the evil of these places, of the miseries of them, we shall hear more presently. Our author, Mr. Jacob A. Riis, asserts again and again that the slums make the disease, the crime, and the wretchedness of New York:-- In the tenements all the influences make for evil, because they are the hot-beds that carry death to rich and poor alike; the nurseries of pauperism and crime, that fill our gaols and police-courts; that throw off a scum of forty thousand human wrecks to the island asylums and workhouses year by year; that turned out, in the last eight years, a round half-million of beggars to prey upon our charities; that maintain a standing army of ten thousand tramps, with all that that implies; because, above all, they touch the family life with moral contagion. Well, that is what the American writer thinks of the tenement system--of the New York slums. _Now_ comes the important question, What is the extent of these slums? And on this point Mr. Riis declares more than once that the extent is enormous:-- To-day (1891) three-fourths of New York's people live in the tenements, and the nineteenth century drift of the population to the cities is sending ever-increasing multitudes to crowd them. Where are the tenements of to-day? Say, rather, where are they not? In fifty years they have crept up from the Fourth Ward Slums and the Fifth Points, the whole length of the island, and have polluted the annexed district to the Westchester line. Crowding all the lower wards, where business leaves a foot of ground unclaimed; strung along both rivers, like ball and chain tied to the foot of every street, and filling up Harlem with their restless, pent-up multitudes, they hold within their clutch the wealth and business of New York--hold them at their mercy, in the day of mob-rule and wrath. So much, then, for the extent of these slums. Now for the nature of them. A New York doctor said of some of them-- If we could see the air breathed by these poor creatures in their tenements, it would show itself to be fouler than the mud of the gutters. And Mr. Riis goes on to tell of the police finding 101 adults and 91 children in one Crosby Street House, 150 "lodgers" sleeping "on filthy floors in two buildings."