The document describes the poor living conditions and lack of sanitation in industrial towns in the 19th century that contributed to the spread of disease like cholera. Rivers were polluted by sewage and industrial waste and used for drinking water. Cesspools leaked into water supplies. Overcrowded housing with no running water or ventilation made it easy for diseases to spread. Cholera arrived in 1831 and could kill within days, spread through contaminated water. People did not understand germ theory and blamed smells and bad air for disease.