Complex sentence: Decimus Alfred Ball (1836-30 June 1890) was an upholsterer and furniture dealer in nineteenth century London who was also a landlord on the Northampton Estate in Clerkenwell, London, known for the overcrowding and poor condition of his properties.
Split into simpler sentences: Decimus Alfred Ball (1836-30 June 1890) was an upholsterer and furniture dealer in nineteenth century London. He was also a landlord on the Northampton Estate in Clerkenwell, London, known for the overcrowding and poor condition of his properties.