The civic infrastructure overseeing the management of London's sewers had gone through several changes in the 19th century. In 1848 the Metropolitan Commission of Sewers (MCS) was established at the urging of the social reformer Edwin Chadwick and a Royal Commission. The Commission superseded seven of the eight authorities that had managed London's sewers since the time of Henry VIII; it was the first time that a unitary power had full control over the capital's sanitation facilities. The Building Act 1844 had ensured that all new buildings had to be connected to a sewer, not a cesspool, and the commission set about connecting cesspools to sewers, or removing them altogether. Because of the fear that the miasma from the sewers would cause the spread of disease, Chadwick and his successor, the pathologist John Simon, ensured that the sewers were regularly flushed through, a policy that resulted in more sewage being discharged into the Thames.