This satirical cartoon, published in Punch magazine, posits the existence of a new kind of microscope known as the Molecular Magnifier, which will show you the exact chemical make-up of a drop of water down to the basest constituent. The basest constituent turns out to be London’s political class: ‘Creatures – who shall name them? Things in human shape – in all appearances London citizens – aldermen, deputies, common councilmen – are seen disporting in the liquid dirt as in their native element.’
In the 19th century, the River Thames was one of the most notoriously polluted stretches of water in the world. It had been common practice for centuries to dump sewage direct into the river. But London’s population doubled between the 1801 and 1851 censuses, meaning that water-borne diseases such as cholera and typhoid went from localised outbreaks to epidemic scale more often.
In 1858, ‘The Great Stink’ occurred – a smell so foul emanating from the Thames that the Houses of Parliament had to be shut for several weeks. In response to the Stink, the government proposed new underground sewers for central London, under the stewardship of civil engineer Joseph Bazalgette (1819-1891). Bazalgette’s sewer network had the unintended consequence of providing clean drinking water to central London for the first time, which greatly reduced the number of infectious epidemics.