Goodbye, Sodium

An Edward Hopper-esque atmosphere on the packaging for Corgi's lamp standards kit.

I was fascinated by some strange things as a child. Pylons and cooling towers to name but two, and both from an extremely early age. For some reason, I found various aspects of the man-made environment intriguing, and none more so than street lights. I was reminded of this only last week, when, at twilight, I exited the M1 at Junction 24A. Along the sliproad leading up to the roundabout, the streetlights were glowing a soft shade of pink indicating that they had only just come on. Set against the misty pinkish-blue of the twilight, it made for an atmospheric moment, and one which I realised, with a pang of nostalgia, may never happen again. 

The reason for this is quite simple: LPS (Low Pressure Sodium) street lamps – the ubiquitous orange type that have dominated Britain’s major roads since the 1950s – are being phased out. As of 2019, the last factory producing the lantern units closed, and no more will be made. Anyone who has been out after dark on our major roads in the past few years can’t have failed to notice that the old ‘orange’ night time atmosphere is slowly disappearing, with modern LED lamps taking the place of the older units. Presumably this is being done for reasons of cost efficiency as much as anything else, and the improved colour spectrum of LED lights is claimed to bring benefits in road safety. I’m sure this is true, but I still regret the passing of the old sodium vapour lighting columns.

As a child, two aspects of street lights fascinated me: their colour, and the style of the lighting columns themselves. There was one right outside our house in Lichfield, a concrete column with right-angled bracket, on which was mounted a small, rectangular lamp. When first lit at twilight, the lamp glowed a soft pink, gradually acquiring the distinctive orange hue of sodium. The pink glow has a technical explanation: this initial colour comes from what’s known as ‘Penning mixture’, a blend of gases – usually helium or neon with xenon – used as a ‘starter’ to warm the metal sodium inside the lamp. I saw these colours in terms of confectionery: a strawberry Spangle, followed by an orange Spangle.

The original 1950s column was still in place outside our old home when I took this photo in 1980.
Needless to say, it has long since been replaced.

Not all street lamps were orange, though. Our dad provided the explanation: orange street lamps like the one outside our house were ‘sodium vapour’ whilst the greenish-white sort I’d seen elsewhere were ‘mercury vapour’. The latter were more often to be found on smaller suburban streets, typically mounted on distinctive metal columms, often quite ornate in appearance, topped by a ‘swan-neck’ lamp bracket. In the 1960s, however, mercury lamps could still be found on major roads around the country, to which they lent a ghostly greenish-white light (as mentioned by C.P. Snow in his Strangers and Brothers sequence of novels). Eachelhurst Road in Erdington, which we regularly travelled along on visits to our grandparents, was one stretch of highway I recall seeing under mercury vapour, the lamps sitting atop tall metal columns painted green that probably dated from the 1940s or 50s. Increasingly, though, sodium was becoming the norm.

On trips in our dad’s car at night, I would marvel at the sheer variety of lighting columns. On our grandparents’ road, the lanterns had a distinctive ‘witches hat’ or flying saucer appearance, whilst along the major roads leading into Birmingham a curious suspension system was still in use, whereby a single lantern hung over the middle of the carriageway, slung on chains between two columns mounted at the roadside: a configuration which I believe may have been associated with facilities for tram wires. Around Walsall, where there had definitely been ‘column-sharing’ between lighting and tram wires, one could still see examples of lamps on long metal brackets extending from the poles, some of which still had their old electric insulators and even wires attached. Around more prestigious areas, such as civic buildings, a ‘posh’ type of street lamp predominated. In Birmingham, these took the form of fluted metal columns, painted a discrete powder blue, topped with huge lighting units that gave out a white neon light (sodium was evidently too proletarian for such locations). Still further up the scale of prestige were the lamps to be found around the Cathedral and along Colmore Row in Birmingham City Centre, which employed the same pale blue fluted columns, but were topped off by columnar lights which stood upright. These units, known as ‘Festival’, were manufactured by a local company, REVO, based in Tipton. Few if any survive today, with some of the last known examples being the so-called ‘Richardson Candles’ of Cambridge.

Sourced from http://www.simoncornwell.com/lighting/collect/columns/index.htm

If we ever ventured further afield, I would always notice variations in the style of lamp standards, as civic authorities all tended to use different, often local sources of supply. Some of the older survivors were often extremely ornate, with baroque styling, but these struck me as excessive, and I prefered the more minimalist designs that had been introduced in the post-war era. If I had a favourite style of street light, it was surely the twin-lamp column, as seen so often on the central reservations of dual carriageways, on motorways, and at roundabouts and major road junctions.

I even had toy street lights bought for me, partly to add realism to games with toy cars but mostly because I liked them so much. Corgi offered a ‘kit’ of modern sodium lighting columns (to say it was a ‘kit’ was a bit much: all one had to do was to plug the column into a metal baseplate and attach the plastic lantern to the top), whilst Dinky toys had their own equivalent. Lego also provided street lights to enhance its plastic block environment. Needless to say, none of these examples actually worked, although electric versions would later become available for use on model railway layouts.

Toy street lamps: Dinky, far left/ unknown centre/ Corgi far right/ Lego, foreground

Like so many other items of street furniture, street lamps are somewhat ephemeral. Although installations often endure for decades, wear and tear and the failure of lanterns ensures that most will in time be replaced. 1960s columns were still a common sight on most arterial roads until well into the 1990s, and odd survivors can still be found, usually in overlooked corners that have escaped the ravages of modern redevelopment. I live on a major road whose concrete lighting columns date to the early 1980s and are almost certain to be replaced in the not too distant future. The lanterns are still the old LPS type, which lends a rather 1970s orange vibe to the night time environment.

Despite my abiding interest in street lights, it wasn’t until the age of maybe 13 that I became aware of one of the peculiar characteristics of sodium light: it has a very narrow spectrum, which renders all colours in shades of grey. I first noticed this whilst trying to read a TV21 Annual in the back of our dad’s car on an evening in 1974, when I noticed that the colour pictures in the book appeared monochrome under the light from the passing streetlamps. Sodium does present one distinct advantage over lanterns with a wider spectrum, in that it causes less ‘light pollution’. Astronomical observatories are able to filter out sodium light to give them a clearer view of the night sky, but this cannot be done with modern LED units.

It seems a pity that modern designers can’t hold a (Richardson) candle to those of the 50s, 60s and earlier eras, and contemporary lighting columns are unremarkable in appearance. Practicality (and cost, one assumes) has won out over asethetics. Shame.