What was London like in the 19th century?
Rather smokier and smellier than today. Remember that people were burning wood or coal in their fireplaces, and horses were the main means of motive power until the advent of the railways. Sanitation was better than in earlier centuries, and proper sewers were being constructed (after the Great Stink of 1858) but the Thames was still pretty polluted. Medicine was fairly good, with anaesthetics and antiseptics being in use by mid-century, but still a lot of incurable diseases. Quite a wide gap between rich and poor – compare the East End and West End! Have a look at Liza Picards book about Victorian London as an introduction.