7
ON WATER AND OTHER FLUIDS
A bloody account of urban circulation
Louise Pelletier
In 1628, English physician William Harvey (1578–1657) introduced one of the most celebrated contributions to physiology: the notion of the full circulation of blood in living beings. His treatise, On the Motion of the Heart and Blood in Animals (De Motu Cordis et Sanguinis) gave an account of the double circulation of the blood and the motions of the heart.1 Combining observations, experiments, and measurements, Harvey looked at the heart not as a spiritual seat of the soul, but as a pump that could be analyzed in mechanical terms. Harvey argued that the pulsation of the arteries depends upon the contraction of the left ventricle, while the right ventricle propels the blood into the pulmonary artery. Blood is pumped around the body by the heart, and once it comes back, it is circulated in a closed system through the lungs before being returned to the main circuit.
Harvey investigated among other things the effect of ligatures on blood flow and established that a tight tourniquet fasten on the triceps would interrupt blood flow from the arteries and the veins, causing the forearm to turn cool and pale from lack of blood, while above the ligature it becomes warm and swollen. By loosening the tourniquet slightly, blood flow is restored only from the arteries because they are deeper than the veins. Consequently, the opposite effect occurs in the lower part of the arm that becomes engorged with blood, turning warm and swollen. This experiment also made the veins more visible as they were distended with blood. By pushing on the veins down the arm, Harvey noticed that the flow was interrupted at various intervals by little bumps (identified by his teacher Hieronymus Fabricius as valves). But when he pushed upwards, the flow was not interrupted (Figure 7.1). He noticed the same effect in various veins of the body, except those of the neck where blood flows downwards – towards the heart – rather than upwards. Harvey concluded that valves allow blood to flow in one direction only – that is toward the heart.
Figure 7.1 William Harvey, De Motu Cordis et Sanguinis (1628), plate showing the effect of ligatures on blood flow
In H2O and the Waters of Forgetfulness, Ivan Illich explains how Harvey’s discovery of blood circulation transformed our understanding of the human body, but it also influenced our perception of society and the city as living organisms. Around the middle of the eighteenth century, the notions of wealth and money were “spoken of as though they were liquids” and began to circulate. Social hierarchy came to be imagined in terms of connections as a system of conduits. “Liquidity is a dominant metaphor after the French revolution; ideas, newspaper, information, gossips and – after 1880 – traffic, air and power circulate.”2 If toward the end of the seventeenth century, the removal of fecal matter from the corridors of the Palace of Versailles and the streets of Paris was at best a weekly procedure, during the Enlightenment, cities became perceived as evil-smelling places that could no longer be tolerated.3 In fact, until the middle of the eighteenth century, it was common practice to throw bodily wastes into open spaces such as the Cemetery of the Innocents in Paris. The city gradually became understood as a body through which water ought to circulate without interruption in order to wash it from its impurity, its wastes. Thus, the circulation of air and water became an architectural concern long before the remodeling of Paris by Baron Haussmann in the nineteenth century.
Flowing beneath the pavement
Pierre Patte (1723–1814), a French architect under the reign of Louis XV, is credited for having been the first to design a modern sewer system for Paris to manage not only drinking water, but also rain and wastewater. Accordingly, he devoted an entire chapter of one of his treatises on what he calls “the corrupted distribution of cities” – “Considérations sur la distribution vicieuse des Villes,” in which he expresses the virtues of air and water circulation, but where he also speculates on the working of the guts of the city.4 His interest in the subterranean domain is made explicit from the very beginning, since the title page of his treatise dedicated to The Most Important Objects of Architecture depicts different monuments, ornaments and a public square, but most importantly, an arch on the bottom left of the image that leads to the underground, and incidentally, announces the first chapter of the book (Figure 7.2).
Patte began his reflections on circulation by acknowledging the role of tradition in first choosing the site of a city by referring to Vitruvius who recommended checking the liver of animals to see if they were healthy.5 Patte stresses the importance of knowing the composition of soil in order to determine its fertility, but also its propensity to earthquakes. Yet, he deplores that founders never seem to pay attention to these considerations, as they are more concerned with political reasons, taking possession of a strategic route; the confluent of two rivers; a strategic commercial position.6
Figure 7.2 Pierre Patte, Mémoires sur les objets les plus importants de l’architecture (1769), detail of the frontispiece
Patte asserts that never before has a city been laid out with the purpose of insuring “the well being of its inhabitants, of preserving their life, health, goods, and for insuring the safety of the air and their homes.”7 In any big city, what is most striking, he complains, is to see from all parts flowing excrements and wastes in open streams before continuing into the sewage system, and exhaling in its path all sorts of nauseous smells. Furthermore, the blood from slaughterhouses runs in the middle of the street; entire neighborhoods reek of waste from latrines; hospitals and cemeteries perpetuate epidemics and exhale the germs of sickness and death in the houses. Elsewhere, he says, one can notice that rivers that cross the cities and whose water serves to quench the thirst of its inhabitants are also receptacles of the cesspools and of all the refuse. When it rains, water washes off the roofs transforming the streets into rivers of mud. In short, cities are the embodiment of filthiness, infection and disease. Moreover, cities are often the prey of other calamities such as engulfing fires, floods and earthquakes. The purpose of his book, therefore, is to imagine how to take advantage of the elements, to control them for the benefit of men and to ensure the healthiness of cities and the happiness of its inhabitants.8
In order to attain such ideals, it is foremost important to ensure that cities be as compact as possible, and the trades and crafts that create smell and noise such as tanneries, tripe shops, blacksmiths, edge-tool makers, laundress, hostelry for public transportation, etc., should be placed beyond the edge of cities in suburbs. He advises that slaughterhouses as well as their stables also should be relegated to the outskirts of cities to prevent herds of cattle crossing the streets causing embarrassment for all.9 This is indeed the beginning of industrial urban sprawl. According to Patte, a twenty-five foot wide channel would surround the suburbs and would communicate with the river crossing the city at its entrance and exit so as to ensure air circulation. We should place hospitals and cemeteries beyond the suburbs on elevated and well-aired location to prevent the spread of diseases, he warns, and forbid the construction of houses on bridges as they are found in Paris, because they stop the flow of air on rivers that serve to clean the city. Ventilation and ease of circulation between different areas is set as a priority.10
The cleanliness of a city should be one of its principal ornaments, Patte argues. However, experience shows that it is never the case; no matter how much effort and money is invested, large cities continue to exhale bad smell coming from polluted water from various industries or trades, hospital, cemeteries, latrines, etc. Before solving the problem of how to purge cities from their harmful smells, however, it is necessary to understand the manner in which the transportation of water is administered; and only by combining water and sewage conduits can we expect to find a solution, he writes, again echoing the dual circulation system first introduced by Harvey.11
Patte analyzes different transportation systems made of lead pipes, wood and even clay conduits placed two feet below ground. Given their perpetual failure, he comes to the conclusion that the entire system has to be redesigned from scratch. He suggests an underground aqueduct six feet wide by seven feet high, placed five feet under street level. Two iron pipes located at four feet from the bottom of the aqueduct on little shelves of about fourteen inches would take the water from various reservoirs to the public fountains and houses without risking being crushed by horse carriages (Figure 7.3). That water would serve for everyday use, for bathing (an early mention of such domestic activity) or to drink. The system would also connect individual latrines to the cesspool and use rainwater to clean the system.12 Sewage would drain to the bottom of the cesspool into another aqueduct parallel to the river gathering sewage from all streets, itself draining into the river outside the city. As in a living organism where the oxygenated blood runs side by side with the vitiated blood, fresh water runs together with sewage in a complex system of fluid discharges.
