Here's what he showed:
* Overcrowded and unsanitary tenements: Riis's photographs and descriptions brought to light the cramped, disease-ridden, and dangerous conditions in which many poor families lived. They shared rooms, lacked proper ventilation, and were exposed to filth and lack of basic amenities.
* Poverty and its impact on children: Riis highlighted the struggles of children growing up in poverty, including their lack of education, exposure to crime, and early entry into the workforce. He showed how poverty trapped people in a cycle of hardship and limited opportunity.
* The plight of immigrants: New York City was a major immigration hub at the time, and Riis's work exposed the difficulties faced by newcomers who were often exploited and marginalized. He showed how poverty and lack of resources contributed to crime and social unrest.
* The role of social injustice: Riis's work aimed to challenge the prevailing social order and expose the injustices that led to poverty. He argued that society had a responsibility to address the needs of the poor and create a more equitable system.
Through his powerful images and stark descriptions, Riis's book helped to raise awareness of the plight of the poor and contributed to social reforms that aimed to improve living conditions in New York City and beyond.