Here we have another somewhat gritty narrow back street. It is difficult to tell whether the large arch to the right is an opening into a workshop or a passageway to another narrow street. If the former, then the street would have a more commercial character.
Notice the ornate lamp on the left, almost certainly still a gas lamp. Starting in the 1830s, manufactured gas began to be adopted for street lighting, and this practice expanded rapidly during the remainder of the 19th Century and continued until electricity began to replace it. Gas light and standard tungsten incandescent lamps have many advantages over the later gas-discharge lamps that have now become nearly universal. Mantle-type gas lamps give a full-spectrum white light that is not too bright. Incandescent lamps, which would have soon replaced the gas mantle in this fixture, were not terribly different, except that their spectrum is shifted towards red and is quite deficient in blue. The resultant warm light might even be regarded as an improvement over the more balanced white of the gas mantle.
In the last 50 years, the quality of city illumination declined sharply. First came the shift to mercury-vapor lamps (which have a discontinuous spectrum far too rich in green and blue) and then to low-pressure sodium lamps with their characteristic orange light that is almost wholly lacking in blue. Venice, however, for the most part elected to retain its incandescent street lighting, since it is more attractive and because high the levels of illumination needed by car drivers is not required.
The bad quality of the light was not the only problem, however. The old cast iron lamp poles, which were always made with an eye for beauty, were replaced by cheap aluminum extrusions topped with the standard "cobra head" fixture. This system has nothing to recommend it except very bright illumination at an irreducible cost. Because the spectrum is so poor, many colors cannot even be recognized under its light, and people always look terrible under its glare.
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