This post is a brief review of the development of street lighting from medieval times to the present, introducing the technologies and characteristics of each and every period. In order to better understand the state of street lighting in our streets today. I had to figure out where it all began and how we evolved to the current situation. To understand the field I had to learn of its roots and so comprehend the problems that developed over the years. I also wanted to know what experiences that street lighting provided over the years and what remains of them today and what was the relationship between street lighting and humans in space during various periods? It should be noted that although the review is carried out according to the period discussed there was always an overlap between the different technologies over time.
Ancient & Medieval Times The initial purpose of street lighting was a function of security. It was used by the Greek and Roman civilizations, utilizing oil lamps, mostly because they provided long lasting and moderate flames. The Romans had a “laternarius”, which was the term for a slave responsible for lighting up the oil lamps in front of their villas. This task was kept up to the Middle-Ages when the “link boys” escorted people from one place to another. Each evening, the medieval community prepared itself for dark. At sunset, people began going indoors, locking all entrances. First the city gates, which had been opened at sunrise, were closed, later the same thing happened in individual houses.
16th Century The first attempts to create permanent street lighting were made in Paris in the sixteenth century. By a parliament decree, during the winter months, a lantern should be hanging out under the level of the first floor windowsills before six o’clock. It was to be placed in such prominent position so that the street received sufficient light. This “navigation lights” gave the city streets structure and order by putting the attention on the volumes, to the borders that created the space. This system also allowed individual houses to be recognizable by night.
17th Century In the late seventeenth century, lanterns were mounted on cables above the streets rather than on the houses, in order to “control the streets”. The diversity of private lanterns was replaced by standard lanterns, consisting of a candle in a glass box. Initially, 2,700 lanterns were installed in Paris. In 1700 there were more than 5,000, and by the second half of the eighteenth century the number had risen to about 8,000.
The lanterns were attached to cables strung across the street so that they hung exactly over the middle of the street, like small suns. To control the precise time at which they should be lit or extinguished lighting schedules were made. These calculated the exact times of sunrise and sunset, as well the hours of moonlight for each month. Early on two lanterns were put in the shorter streets, one at each end. In longer streets an additional lantern was placed in the middle. Over time the variable distance between lanterns was standardized and reduced to every third house. Later the brightness of the lanterns was also improved by using reflectors and changed from candles to oil lantern with several wicks.
End of 17th Century -Oil Street Lighting In 1669 Jan var der Haeyden developed an oil lantern for street lighting, which was first used in Amsterdam. The lanterns were hung in the middle of streets using transverse cables. In open spaces (squares, gardens...) they were hung on hangers or brackets attached to iron. The lanterns were set at 5 meters above ground and were lit and monitored during the night by employees, who were assigned 20 lanterns each. In 1694, in th
e city of London, Edward Heming was granted a licence to hang an oil lamp in front of every tenth house from 6pm to midnight between Michhaelmas and Lady Day. At that time, there already was talk of energy conservation and in 1788, oil guts were replaced by rapeseed oil, which was less expensive, less smelly and provided a whiter flame. Many problems remained. The flow of burning oil caused many accidents; lanterns always shed unpleasant smells and were more likely to extinguish in a gale.
19th Century- Gas Lighting In 1791, French Philippe Lebon discovered the principle of light by hydrogen gas carbon. In 1792, the Scotsman William Murdoch and French JP Minckelers made gas lamps used with the principle of distillation of coal in a closed chamber. However, only after more than 20 years of various experiments did the industrial production of gas lanterns really begin. The first public street lighting with gas was at Pall Mall, London on January 28, 1807. In 1812, Parliament granted a charter to the London and Westminster Gas Light and Coke Company, and the first gas company in the world came into being. Less than two years later, on December 31, 1813, Westminster Bridge was lit by gas. The Earliest lamps required a lamplighter who toured the town at dusk, lighting each of the lamps separately, but later designs employed ignition devices that would automatically strike the flame when the gas supply was activated. The first street lighting lanterns were set solely on wall brackets or were suspended. In 1830 the first candelabra appeared. It was around 1850 that lighting truly started to spread throughout France. Candelabra were placed all over the country, making way for coexistence between oil lighting and gas lighting. The candelabra had the advantage of having its gas conveyed by pipes. Initially, manufacturers of lamps were more or less free to manufacture their own implements, but after numerous accidents due to poor quality of some candlesticks, they were asked to produce only iron candelabra, which grew stronger and stronger. In Paris around 1840, in order to take into account the moonlit nights on which street lighting is normally reduced, two types of street lanterns had developed. Permanent lanterns which burned from sunset to sunrise, and variable lanterns which were lit only when the moon-light was not bright enough to light the streets.
End of the 19th Century- Moon Light Towers Moonlight towers are lighting structures designed to illuminate big areas of a city at night. The structures were popular in the late 19th century in cities across the United States and Europe, and were most common in the 1880s-1890s. In some places they were used when standard street-lighting systems — using smaller, shorter, and more numerous lamps — were impractically expensive. Elsewhere they were used in addition to existing gas street lighting. The towers were designed to illuminate areas of several blocks at once. Arc lamps were the most common method of illumination, known for their exceptionally bright and harsh light. As incandescent electric street lighting became common, the prevalence of moonlight tower systems began to wane.
End of the 19th Century - Electric Street Lighting The first electric street lights employing arc lamps were developed by the Russian Pavel Yablochkov in 1875. This was a carbon arc lamp utilizing alternating current, which ensured that the electrodes burnt down at the same rate. Yablockov candles were first used to light the Grand Magasins de Louvre, Paris where 80 of them were deployed. This improvement was one of the reasons why Paris earned its “City of Lights” nickname. Soon after, experimental arrays of arc lamps were used to light Holburn Viaduct and the Thames Embankment in London - the first electric street lighting in Britain. More than 4,000 were in use by 1881, though by then an improved differential arc lamp had been developed by Friederich von Hefner-Alteneck of Seimens & Halske. The technology of these lamps was not yet fully developed, their use was very energy consuming, and the light output unsatisfactory, therefore a poor value for money compared to gas lighting. Not until the early 20th century through the work of Thomas Edison, who took the precaution of filing the patent for this technology, did the electric lights began to compete with gas lighting. Between 1910 and 1940, much work of electrification of major cities was undertaken, and electric lamps using incandescent lamps were gradually replacing the gas lanterns. The last gas lanterns disappeared from France in the mid-1960s.
The first discharge lamps that were heavily used in street lighting emerged in the 1930s: •These came in the form of a tube in whose ends were placed two electrodes. The tube contained mercury gas and its inner wall was covered with a fluorescent powder. They quickly took the name of fluorescent tubes and their general use started in 1945. •In 1932 the first sodium vapour lamp appeared. In its debut it was presented as a long light bulb, 10 centimetres wide. It emitted a light radiation by passing an electric arc in a medium rich in sodium. This type of lamp emitted a yellow-orange light.
Facilities using sodium lamps, today called low-pressure sodium lamps, started developing in 1950. Fluorescence and sodium coexisted; each technology having its own advantages and disadvantages: •The balloons had a fluorescent colour rendering an index higher than sodium lamps. This means that it is easier to perceive colours in a street at night if they are lit by fluorescent balls. Sodium lamps produced only monochromatic light, which makes it a difficult colour to perceive if surrounded by a background. •Sodium lamps were more energy efficient than the fluorescent balls. This means that at the same power consumption, a sodium lamp provided much more visible light than fluorescent ball. Between 1950 and 1970 Sodium lamps were installed purely in a functional form such as on highways, major intersections and industrial sites. Monochromatic light provided by sodium nevertheless has another important advantage; its influence is much less dispersive case of humidity and fog.
Metal halide lamps The first metal halide lamp was put on the market in the U.S. by General Electric in 1961. It used a mixture of mercury and iodides (negative ions) of sodium. The light obtained, having a white with pink hue, was unsatisfactory. Work carried out in 1965 was far more adequate. The lamp emitted light of a bluish-white colour. The 1990s saw the spread of metal halide lamps in public lighting. Two main reasons explain this phenomenon9: Firstly, from around 1985, halide lamps emitted different shades of white. These were distinguished in particular lamps emitting a cool white (colour light bluish-white), neutral white light (almost pure white) and warm white light (white to beige highlights). Second, in 1994, halide lamps with ceramic burners were introduced. The quartz discharge tube was replaced by a piece of ceramic in a much more compact form, increasing the lifespan of these lamps by 50% and providing a light that degraded less over time. The many advances in lighting technology and new opportunities they have created had a large influence over time. Until the early 20th century when lighting was reserved only for citizens in cities, most of the achievements of public lighting were brought in from small towns. The facilities were very expensive and so installed for a population that had the means to afford them. After the First World War electric streetlights began to spread and the developments of manufacturers were increasingly brought to the big cities. Until about 1970, requirements for public lighting were primarily functional. Its role was almost exclusively reserved for the purpose of security. Customer requirements were simple: to shed light, at the lowest possible price. The late 1960s saw the emergence of new needs in terms of lighting, putting more and more emphasis on aesthetics. In this context two major trends have emerged: The style lighting and set mast + lanterns.
Generalization of lighting style The aesthetics of the products in daytime had become more and more important. In this framework developed what was promptly called “style lighting”. The meaning of this is the manufacture of new products by reusing the design of old lanterns and adapting it to electric lighting. It is difficult to date the appearance of lighting styles as most major cities had not replaced some of their old gas lanterns by the late 1950s.